Message Passing Interface (MPI) is a standard library interface for writing parallel programs. The MPI specification is broadly used for solving engineering and scientific problems on parallel computers, and MPICH2 is a popular MPI implementation developed at Argonne National Laboratory. The scalability of MPI implementations is very important for building high performance parallel computing applications. The initial TCP (Transmission Control Protocol) network module developed for Nemesis communication sub-system in the MPICH2 library, however, was not scalable in how it established connections: pairwise connections between all of an application's processes were established during the initialization of the application (the library call to MPI_Init), regardless of whether the connections were eventually needed or not. In this work, we have developed a new TCP network module for Nemesis that establishes connections on-demand. The on-demand connection establishment scheme is designed to improve the scalability of the TCP network module in MPICH2 library, aiming to reduce the initialization time and the use of operating system resources of MPI applications. Our performance benchmark results show that MPI_Init in the on-demand connection establishment scheme becomes a fast constant time operation, and the additional cost of establishing connections later is negligible. The on-demand connection establishment between two processes, especially when two processes attempt to connect to each other simultaneously, is a complex task due to race-conditions and thus prone to hard-to-reproduce defects. To assure ourselves of the correctness of the TCP network module, we modeled its design using the SPIN model checker, and verified safety and liveness properties stated as Linear Temporal Logic claims.

This Bachelor’s degree thesis has been performed on behalf of Upplands Lokaltrafik. The thesis aims to suggest a design of a stand-alone renewable power supply system for the bus stops in Uppland. Because of reorganization of Upplands Lokaltrafik and a change in the electricity act they now have to make the decision of either having the future bus stops connected to the electricity grid, with the requirement of installing an electricity meter at each bus stop, or to implement an off grid solution. Upplands Lokaltrafik has a goal of doubling the number of passengers until 2020 and as a part of reaching this goal the bus stops will be designed with electrical features. This thesis also aims to investigate the electricity demand for these future bus stops. The result of the study shows that a connection to the electricity grid and installation of an electricity meter means an investment cost of approximately 83 500 SEK or 123 500 SEK depending on how far cables have to be drawn. The solution with a photovoltaic system with a 180 Wp solar panel would result in an installation cost of 18 500 SEK, which would be both cheaper and more sustainable for the future. However, a photovoltaic system means higher maintenance and a higher risk of destruction. Depending on choice of batteries and the slope of solar panels, both maintenance and risk of vandalization could be diminished.

This thesis investigates TCP connection management mechanisms in order to understand the behaviour and improve the performance of Internet servers during overload conditions such as flash crowds. We study several alternatives for implementing TCP connection establishment, reviewing approaches taken by existing TCP stacks as well as proposing new mechanisms to improve server throughput and reduce client response times under overload. We implement some of these connection establishment mechanisms in the Linux TCP stack and evaluate their performance in a variety of environments. We also evaluate the cost of supporting half-closed connections at the server and assess the impact of an abortive release of connections by clients on the throughput of an overloaded server. Our evaluation demonstrates that connection establishment mechanisms that eliminate the TCP-level retransmission of connection attempts by clients increase server throughput by up to 40% and reduce client response times by two orders of magnitude. Connection termination mechanisms that preclude support for half-closed connections additionally improve server throughput by up to 18%.

The purpose of this study is to develop an approach that considers fire as a load in the design of structures. Recent studies of the full-scale fire tests in Cardington, UK and the World Trade Centre collapse have shown that the behaviour of steel structures in fire when assembled into a frame differs from that measured or predicted by fire testing of individual structural elements, revealing the importance of accounting for realistic fire loads in the design of structures and the potential inadequacy of fire testing individual elements as employed by current building codes. Yet, there has been limited basic research and development to allow consideration of fire as a load in the analysis and design of structures. In response to this much needed work, this thesis develops an approach to include fire as a load in the analysis of a 2-bay by 2-storey structure when a semi-rigid connection is exposed to thermal loads typical of those that might be encountered during a real fire. The structural fire analysis is principally based on incorporating moment-rotation-temperature data for the connection, as found in archival literature, into a structural analysis software package developed at the University of Waterloo. The software employs a modified Displacement Method for analyzing structures, which involves the computation of stiffness reduction factors that represent the deterioration of strength of the structural elements as they are subjected to various loads. By modifying the moment-rotation-temperature data for a semi-rigid connection into a form recognized by the software, a fire load is simulated by incrementally elevating the temperature of the affected steel connection. In this way, a fragility analysis of the entire structure under fire load is conducted. A series of example calculations are presented for cases in which the semi-rigid connection is exposed to increasing temperatures of 20°C, 200°C, 400°C and 600°C. The analysis showed that as the connection is heated, it is weakened, and the steel structure undergoes a redistribution of moments from the heated connection to other non-heated elements within the framework, which is essentially a form of fire-resistance of the assembled structure that unassembled members in isolation do not have. The study also demonstrated that the experimental moment-rotation-temperature data reported in archival literature can be incorporated into the structural analysis, and that additional force-deformation data obtained from further experimental work or through finite-element analyses would allow the study to be extended to analyze the effects of fire loading on other structural elements of an assembled framework. To demonstrate the link between the predicted structural response at different temperatures and the development of a compartment fire, a fire modelling analysis is also performed.

I den här kandidatuppsatsen undersöks storytelling som kommunikationsform på Volvo Personvagnar. Studien presenterar organisationsberättelser som karaktäriserar företaget samt dess funktioner och betydelser. Vidare lyfter studien fram storytelling som verktyg för att påverka en publiks uppfattningar. Inspiration till ämnet inhämtas från nutida forskare och storytelling relateras till kommunikativa uttryck och meningsskapande. Studiens empiri består av intervjuer av anställda på Volvo samt pr-konsulter med inblick i företaget. Empirin innefattar även en semiotisk analys av reklamannonser. Målsättningen är att svara på studiens övergripande problem: Hur arbetar Volvo Personvagnar med storytelling som kommunikationsform för att skapa relationer med sina kunder? Resultatet av studien visar på hur man förhåller sig till storytelling på Volvo, vad man berättar om sig själv samt hur man vill påverka kundernas uppfattning av varumärket. Berättelserna som analyseras i studien beskriver volvoandan, volvokunden, företagsidentiteten och Volvos vilja att förändra varumärket. Vidare analyseras Ycc-projektet, ett initiativ där man aktivt arbetade för att skapa uppmärksamhet och påverka kundernas uppfattningar av varumärket. Slutligen sätts organisationsberättelserna i ett vidare perspektiv där deras trovärdighet och betydelse diskuteras. Studien argumenterar för vikten av att förvalta de värderingar som man tror på och som man vill att andra ska förknippa med organisationen. Vidare diskuteras den problematik som kan uppstå när man som Volvo vill förändra sitt varumärke.

Performance-Based (PBE) and Consequence-Based (CBE) are new approaches to seismic design, evaluation and risk assessment, in which design criteria are devised to achieve stated performance objectives, and regional losses to civil infrastructure are mitigated through selective interventions for critical components of a civil infrastructure. These new approaches give engineers more flexibility in achieving performance goals but require substantial additional computational resources to fully achieve performance goals. As a step toward making such approaches feasible, this dissertation develops a number of computationally efficient methods for performing finite element-based structural system dynamic response analysis and reliability assessment. The Enhanced Uncoupled Modal Response History Analysis (EUMRHA) procedure developed herein is an efficient response analysis procedure to make the analysis of dynamic structural response to earthquakes in the nonlinear range less time-consuming. This technique is used to investigate the potential for aftershocks to cause additional damage to steel moment frame buildings, utilizing a technique designed to enhance the efficiency of Monte Carlo simulation in estimating low-probability events. Relatively simple probabilistic tools are proposed for purposes of rapid structural evaluation and condition assessment of damaged buildings. Finally, an analysis-based inspection scheme based on an associated probability model of connection damage is proposed for assessing the safety condition of existing buildings, and a procedure to assess the likely performance of an un-repaired building during a future earthquake is developed.

Books and printed materials have been used as a major learning content for thousands of years. Nowadays, Smartphone is considered as an important tool for mobile learning. This study designed a learning environment with paper and Smartphone which seamlessly integrates printed materials and digital materials. The idea is to augment the traditional paper-based materials with plenty of digital materials available on the Internet. Furthermore, because both book and Smartphone are with very good mobility, the designed system is also very suitable for mobile learning. Two special mechanisms were designed for supporting learning activities, and their effects on learning performance were evaluated. The first one is learning recommendation which is generated based on the learning portfolio. The second one is automated content connection which can reduce the loading of context switching between printed materials and digital materials so as learners can be more concentrated on learning tasks. A system was designed and implemented for conducting an experiment and data collection. The statistic analysis shows that learning recommendation has a significant positive effect on learning performance; however, the effect of automated content connection on learning performance is not significant. Besides, the questionnaire survey also shows that learners have positive attitude toward the acceptance of the learning system designed in this study. Based on the results, some implications and suggestions are provided for researchers and instructors.

Analysis of aircraft structures are mainly performed by assuming that the structure behaves linearly. In linear finite element analysis, it is assumed that deformations are small, thus geometric nonlinearity can be neglected. In addition, linear analysis assumes that linear constitutive laws applicable, implying that material nonlinearity can also be neglected. One very common type of nonlinearity is associated with the boundary conditions. Contact between two deformable bodies or between a deformable and rigid body are typical examples of nonlinearity associated with boundary conditions. Linear structural analysis, in general, does not include contact analysis. Simplicity of linear analysis in terms modeling, interpreting the results and solution time makes the linear analysis approach very convenient in preliminary design and analysis stage of aircraft structures. However, simplicity of linear analysis may result in unconservative results which may occur due to neglecting the true nonlinear behavior of the structure. In this thesis, one such nonlinear eect called prying load eect on the tensile connections is studied. The eect of prying load on structures are initially described by referencing the analytical approaches presented in the literature. Finite element models of typical bolted connections such as L and T type are generated for various combinations of the chosen design parameters such as bolt diameter, flange thickness, washer diameter and edge distances. Parametric modeling approach is used to perform the high number of finite element analysis which involve contact for the purpose of calculating the prying load. Comparative study of the eect of prying load is then conducted by also including the results presented in the literature. Comparisons of the prying load are done with the experimental results presented in the literature. Series of finite element analyses are preformed for various cases such that eect of geometrical variables and bolt preload on prying ratio can be understood. According to the results obtained, it is concluded that main factors eecting the prying ratio are the distance of bolt center to the clip web, flange thickness of the clip and preload on the bolt where the eect of edge distance of the bolt is insignificant.

<p>I den här kandidatuppsatsen undersöks storytelling som kommunikationsform på Volvo Personvagnar. Studien presenterar organisationsberättelser som karaktäriserar företaget samt dess funktioner och betydelser. Vidare lyfter studien fram storytelling som verktyg för att påverka en publiks uppfattningar. Inspiration till ämnet inhämtas från nutida forskare och storytelling relateras till kommunikativa uttryck och meningsskapande.</p><p>Studiens empiri består av intervjuer av anställda på Volvo samt pr-konsulter med inblick i företaget. Empirin innefattar även en semiotisk analys av reklamannonser. Målsättningen är att svara på studiens övergripande problem: <em>Hur arbetar Volvo Personvagnar med storytelling som kommunikationsform för att skapa relationer med sina kunder?</em></p><p>Resultatet av studien visar på hur man förhåller sig till storytelling på Volvo, vad man berättar om sig själv samt hur man vill påverka kundernas uppfattning av varumärket. Berättelserna som analyseras i studien beskriver volvoandan, volvokunden, företagsidentiteten och Volvos vilja att förändra varumärket. Vidare analyseras Ycc-projektet, ett initiativ där man aktivt arbetade för att skapa uppmärksamhet och påverka kundernas uppfattningar av varumärket.</p><p>Slutligen sätts organisationsberättelserna i ett vidare perspektiv där deras trovärdighet och betydelse diskuteras. Studien argumenterar för vikten av att förvalta de värderingar som man tror på och som man vill att andra ska förknippa med organisationen. Vidare diskuteras den problematik som kan uppstå när man som Volvo vill förändra sitt varumärke.</p><p> </p><p> </p>

Title from PDF of title page. / Document formatted into pages; contains 161 pages. / Thesis (M.S.C.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: Driving piles constitute a large portion of the high-capacity foundations used today. They transfer structural loads to deep bearing strata when adequate surficial soils are not available. The mechanisms required to install these piles generally consist of a hammer, hammer lead, a crane, and various support rigging. This study focused on lead sections, specifically, one which was manufactured by Berminghammer Foundation Equipment, Inc. The dimensions and strength of a lead section must be capable of supporting both the pile driving hammer and the longest anticipated pile for a given site. The strength of the section must be capable of withstanding hundreds of tons in compression and bending. If the lead is operated in a batter, (tilted forward, backward, or sideways) the weight of the hammer and pile causes much more bending than the vertical orientation. / ABSTRACT: The cross-section details for these long steel sections vary from design to design but usually incorporate some form of bolt group, pins, and steel alignment dowels. This thesis focuses on the design, modeling, and testing of such a connection. The motivation of the study stems from a company-wide incentive to standardize the connections used to splice the Berminghammer C15-series lead section. In an effort to verify a proposed connection design, Berminghammer Foundation Engineering solicited the University of South Florida to test a full-sized lead section to failure, while monitoring the splice-connection performance. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.