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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

What power demand does a residential building have? : A study about electricity consumption of a residential building in Knivsta

Ljungqvist, Christina, Lindblom, Emma, Åhgren, Malin January 2014 (has links)
Knivsta municipality is planning a new climate-friendly and environmentally sustainable district called Nydal. The vision is to create a residential area that is minimally dependent on outside sources of electricity. The aim of this research is to evaluate the efficiency and electricity demand of a residential house in Knivsta. A model for the power demand of an apartment house has been constructed, using data for the electricity consumption of one household from Kiruna during a week in April. Data from the Swedish Energy Agency has been used to identify the distribution of electricity for the different loads. This study has focused on the electricity consumption of a family that consist of two adults and one child and their use of home appliances. A comparison between standard appliances and energy efficiency appliances has been made to find out how much the power and their load peaks can be reduced. The total amount of electricity consumption for the residential building’s households is about 93 MWh during a year. By selecting energy efficient appliances in the apartments the total household electricity consumption of the residential building can be reduced by about 55 MWh, which is almost a 60 % reduction per year. The residential buildings load peaks can be reduced. This can be achieved by installing energy efficient products by using Top Ten’s list over the most energy saving household appliances available on the market. Installing LED lamps and HWC driven products also reduces the power demand significantly. By installing HWC driven products in the common washhouse, the residential electricity can be reduced by 29 %. A more environment-friendly lifestyle affects the electric load. The power demand can decrease if buying less power demanding products, but also by using the power demanding products in a more energy efficient way. Knivsta municipality is able to help the tenants in Nydal to increase their knowledge. By increasing the individuals’ knowledge about power demand and energy saving, it is possible to influence individuals’ behavior and with that reduce the electric load.
2

Building load analysis and graphical display as a design tool

Jerome, David 05 1900 (has links)
No description available.
3

Loadcal : a microcomputer simulation for estimating heating and cooling loads for commercial buildings

Cleaveland, John P. 08 1900 (has links)
No description available.
4

Bedload transport in an Oregon Coast Range stream /

O'Leary, Susan Jean. January 1980 (has links)
Thesis (M.S.)--Oregon State University, 1981. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
5

Variations in gravel bed composition of small streams in the Oregon Coast Range /

Adams, James Neal. January 1979 (has links)
Thesis (M.S.)--Oregon State University, 1980. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.
6

Bed load transport in gravel-bed rivers /

Barry, Jeffrey J. January 1900 (has links)
Thesis (Ph. D., Civil Engineering)--University of Idaho, July 2007. / Major professor: John M. Buffington. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
7

Sustained Load Behaviour of Reinforced Concrete Frames

Danielsen, Ronald, C.T. 03 1900 (has links)
Methods are presented for the predication of the short-term and sustained load behaviour of reinforced concrete frames. These procedures are evaluated by an experimental program using a particular structure and loading configuration. The results of two short-term tests and one sustained load test are compared with the analytic predictions. The inadequacy of classical methods of structural analysis for sustained load problems is also discussed. It is concluded that the methods using small elements, numerical integration and successive iterations can provide accurate predictions of short-term and sustained load behaviour of reinforced concrete beams. / Thesis / Master of Engineering (ME)
8

Continuously Providing Approximate Results under Limited Resources: Load Shedding and Spilling in XML Streams

Wei, Mingzhu 18 December 2011 (has links)
" Because of the high volume and unpredictable arrival rates, stream processing systems may not always be able to keep up with the input data streams, resulting in buffer overflow and uncontrolled loss of data. To continuously supply online results, two alternate solutions to tackle this problem of unpredictable failures of such overloaded systems can be identified. One technique, called load shedding, drops some fractions of data from the input stream to reduce the memory and CPU requirements of the workload. However, dropping some portions of the input data means that the accuracy of the output is reduced since some data is lost. To produce eventually complete results, the second technique, called data spilling, pushes some fractions of data to persistent storage temporarily when the processing speed cannot keep up with the arrival rate. The processing of the disk resident data is then postponed until a later time when system resources become available. This dissertation explores these load reduction technologies in the context of XML stream systems. Load shedding in the specific context of XML streams poses several unique opportunities and challenges. Since XML data is hierarchical, subelements, extracted from different positions of the XML tree structure, may vary in their importance. Further, dropping different subelements may vary in their savings of storage and computation. Hence, unlike prior work in the literature that drops data completely or not at all, in this dissertation we introduce the notion of structure-oriented load shedding, meaning selectively some XML subelements are shed from the possibly complex XML objects in the XML stream. First we develop a preference model that enables users to specify the relative importance of preserving different subelements within the XML result structure. This transforms shedding into the problem of rewriting the user query into shed queries that return approximate answers with their utility as measured by the user preference model. Our optimizer finds the appropriate shed queries to maximize the output utility driven by our structure-based preference model under the limitation of available computation resources. The experimental results demonstrate that our proposed XML-specific shedding solution consistently achieves higher utility results compared to the existing relational shedding techniques. Second, we introduces structure-based spilling, a spilling technique customized for XML streams by considering the spilling of partial substructures of possibly complex XML elements. Several new challenges caused by structure-based spilling are addressed. When a path is spilled, multiple other paths may be affected. We categorize varying types of spilling side effects on the query caused by spilling. How to execute the reduced query to produce the correct runtime output is also studied. Three optimization strategies are developed to select the reduced query that maximizes the output quality. We also examine the clean-up stage to guarantee that an entire result set is eventually generated by producing supplementary results to complement the partial results output earlier. The experimental study demonstrates that our proposed solutions consistently achieve higher quality results compared to the state-of-the-art techniques. Third, we design an integrated framework that combines both shedding and spilling policies into one comprehensive methodology. Decisions on the choice of whether to shed or spill data may be affected by the application needs and data arrival patterns. For some input data, it may be worth to flush it to disk if a delayed output of its result will be important, while other data would best directly dropped from the system given that a delayed delivery of these results would no longer be meaningful to the application. Therefore we need sophisticated technologies capable of deploying both shedding and spilling techniques within one integrated strategy with the ability to deliver the most appropriate decision customers need for each specific circumstance. We propose a novel flexible framework for structure-based shed and spill approaches, applicable in any XML stream system. We propose a solution space that represents all the shed and spill candidates. An age-based quality model is proposed for evaluating the output quality for different reduced query and supplementary query pairs. We also propose a family of four optimization strategies, OptF, OptSmart, HiX and Fex. OptF and OptSmart are both guaranteed to identify an optimal solution of reduced and supplementary query pair, with OptSmart exhibiting significantly less overhead than OptF. HiX and Fex use heuristic-based approaches that are much more efficient than OptF and OptSmart. "
9

Design Guidelines for Test Level 3 (TL-3) Through Test Level 5 (TL-5) Roadside Barrier Systems Placed on Mechanically Stabilized Earth (MSE) Retaining Wall

Saez Barrios, Deeyvid 1980- 14 March 2013 (has links)
The use of Mechanically Stabilized Earth (MSE) wall structures has increased dramatically in recent years. Traffic barriers are frequently placed on top of the MSE wall to resist vehicular impact loads. The barrier systems are anchored to the concrete in case of rigid pavement. Nevertheless, in case of flexible pavement, the barriers are constructed in an L shape so that the impact load on the vertical part of the L can be resisted by the inertia force required to uplift the horizontal part of the L. The barrier must be designed to resist the full dynamic load but the size of the horizontal part of the L (moment slab) is determined using an equivalent static load. Current design practice of barriers mounted on top of MSE retaining wall is well defined for passenger cars and light trucks. However, the information of this impact level is extrapolated to heavy vehicle impact. Therefore, the bases of this research is to develop design procedure and to help understand the dynamic behavior of a barrier-moment slab system on top of an MSE wall when subjected to heavy vehicle impact loads. In a first part, numerical analyses were conducted to better understand the behavior of the barrier-moment slab system when subjected to heavy vehicle impact loads. The full-scale impact simulations were used to develop the recommendation for designing and sizing the barrier-moment slab system. In a second part, the barrier-moment slab systems defined to contain heavy vehicle impact loads were placed on top of an MSE wall model to study the kinematic behavior of the system. Loads in the soil reinforcing strips and displacements on the barriers and wall components are evaluated to define recommendation for design of strip reinforcements against pullout and yielding. In a third part, a full-scale crash test on a barrier-moment slab system on top of an instrumented 9.8 ft. (3 m) high MSE wall is described and analyzed. The MSE wall and barrier system were adequate to contain and redirected the vehicle and, therefore, it served as verification of the proposed recommendation. Finally, conclusions are drawn on the basis of the information presented herein.
10

Re-Load lastpall : En jämförelse mellan Re-Load och alternativ lastpall

Engström, Per January 2011 (has links)
Syftet med denna undersökning har varit att underlätta för företaget Re-Load att presentera sin lastpall som produkt för potentiella kunder. Syftet har också varit att stötta Re-Load till att bli licenserad EUR-pall samt att successivt ersätta befintliga lastpallar och långsiktigt exekvera företagets affärsplan. Målet har varit att undersöka produkten avseende lönsamhet, miljöinverkan och hur den påverkade arbetsmiljön. Under-sökningen har genomförts med ett befintligt flöde där produkten använts och utifrån detta kunde en flödesstudie samt en komparativ produktstudie utföras med en alternativ lastpall. Med data hämtat ur detta flöde utfördes en investeringskalkylering, miljöberäkningar, subjektiva intervjuer samt dokumentation. Kalkyleringar och beräk-ningar har redovisats grafiskt för att erhålla ett presentabelt och över-skådligt resultat. Undersökningen visar att Re-Load lastpall har en dyrare grundinvestering men är mer lönsam i längden. Efter 15 måna-der har Re-Load lastpall och den alternativa lastpallen uppnår samma kostnad. Vidare visar undersökningen att pallen släpper ut mindre koldioxid än den alternativa lastpallen i det givna fallet. Resultatet visar också att pallen är mer hållbar än alternativa lastpallar, framförallt gällande tyngre transporter. Slutsatsen är att Re-Load lastpall är en lönsam investering i längden för detta specifika fall, men att resultaten inte bör generaliseras. Slutsatsen visar vidare att pallen har en positiv inverkan på miljön i jämförelse med denna alternativa pall. Detta är knutet till att Re-Load lastpall har en lägre vikt än den alternativa. Jämförelse av pallarna i arbetsmiljön är problematiskt och analyserna visar att Re-Load lastpall saknar utbredning för att kunna göra en betydande inverkan på arbetsmiljön. / The purpose with the investigation has been to support the company Re-Load represent their pallet as a product to potential clients. The purpose has also been to support Re-Load in getting their pallet licensed as a EUR-pallet, gradually replacing existing pallets and over time execute their business plan. The goal has been to study the product regarding profitability, environmental effects and impact on the work environment. The research has been carried out with an existing flow where to product has been used thus allowing a comparative product study with an alternative pallet. Investment calculation, environmental calculating, subjective interviews and documentation were performed with data from the flow. Calculations have been shown graphically to receive a presentable and foreseeable result. The research shows that the Re-Load pallet has a higher investment cost but is more profitable in the long run. After 15 months the Re-Load pallet and the alternative pallet reaches the same cost. Further on the research shows that the pallet discharges less carbon dioxide than the alternative pallet in the specific case. The result also shows that the pallet is more durable than alterna-tive pallets, specifically regarding heavy transports. The conclusion is that the Re-Load pallet is an profitable investment in the long run for this specific case, but the results should not be generalized. The conclu-sion further show that the pallet has a positive impact on the environ-ment in comparison to this alternative pallet. This is related to the Re-Load pallet being lighter than the alternative. Comparison of the pallets in the work environment is problematic and the analysis shows that the Re-Load pallet lacks expansion to make a significant impact on the work environment.

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