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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.
861

Hotel s wellness / Wellness hotel

Kubátová, Aneta January 2018 (has links)
The subject of the project is a new building in the cadastral area of Havlíčkův Brod. The object is designed for 30 persons for accommodation and 52 people in the restaurant. The building is partly basement and has three floors. On the first floor there is a restaurant with guest facilities and a kitchen with facilities for the staff. On the second and third above-ground floor are mainly hotel rooms. In the basement there is technical equipment such as a boiler room, air-conditioning machine and laundry. The object is solved from ceramic blocks POROTHERM. The ceiling is a monolithic reinforced concrete. The roof is flat single-skinned.
862

Kinetik ved løb med dagligdagsprotese og løbespecifikprotese hos transtibial amputerede: Et cross-sectional studie

Grøtner, Katrine, Pham, Huy Hoang January 2020 (has links)
Formål: Formålet med studiet er at undersøge hvordan løb med en dagligdagsprotese og en løbespecifikprotese påvirker kinetik i nedre ekstremiteter hos mennesker med en transtibial-amputation.   Metode: Kinetisk data blev indsamlet ved løbetests, med begge proteser, med et motion capture system og kraftplader i et klinisk ganganalyse lab i Göteborg, Sverige. Deltagere(n=2) udførte løbetests i selvvalgt hastighed, iført refleksive markører. Vertikal GRF, fod progressions vinkel, adducerende/abducerende hofte- og knæmoment udvalgt til videre databehandling.   Resultat: Forskelle i hofte- og knæ adduktions moment og fod progressions vinkel blev observeret mellem de to protesetyper. Momenterne var mindre, når deltagerne løb med den løbespecifikke protese. Forskelle på den amputerede side og den kontralaterale side noteredes ved alle parametre uanset protesetype. Den kontralaterale side havde forøgede værdier sammenlignet med den amputerede side.   Konklusion: Grundet forsøgets størrelse kan vi ikke konkludere, at individer med unilateral amputation i nedre ekstremitet absorberer belastning bedre, når de løber med en løbespecifikprotese fremfor en dagligdagsprotese. / Aim: The aim of this study was to investigate how running with a daily-use prosthesis and a running specific prosthesis affects kinetics in the lower extremities when it comes to people with a transtibial amputation.   Method: Kinetic data was collected through running tests, using both type of prosthesis, with a motion capture system and force plates in a clinical gait lab in Gothenburg, Sweden. Participants (n=2) executed the running tests in a self-selected speed, while wearing reflective markers. Vertical ground reaction force, foot progression angle, hip- and knee moment were selected for data processing.   Results: Differences in hip- and knee adduction moment and foot progression angle were observed between the two types of prostheses. Moments were smaller when participants ran with running-specific prosthesis. Dissimilarity for the amputated side and the contralateral side were noted for all parameters regardless of type of prosthesis. The contralateral side had increased values compared to the amputated side.     Conclusion: Because of the sample size we cannot conclude that individuals with a unilateral lower body amputation absorb load more efficiently when running with a running-specific prosthesis rather than a daily-use prosthesis.
863

Löpa med eller utan skor: en litteraturöversikt över löpekonomi och biomekanik / Running with or without shoes: a systematic review of running economy and biomechanics

Gradin, Christoffer, Jonsson, Jonathan January 2022 (has links)
Bakgrund: Löpning är en populär motionsform i Sverige idag, dock är det vanligt med överbelastningsskador bland löpare och nästan 80% skadar sig på något vis varje år. Diskussion har uppstått bland löpare och forskare kring om barfotalöpning kan förändra biomekaniken och därmed ändra belastningen och minska risken för skador, samt om barfotalöpning kan leda till en förbättrad löpekonomi och påverka löparens prestationer. Syfte: Att undersöka vilken effekt barfotalöpning (inkl. minimalistskor) har på biomekanik mätt med ground reaction force (GRF) och löpekonomi mätt med syreupptagning jämfört med löpning med konventionella skor.  Metod: Systematisk narrativ litteraturöversikt. Litteratursökningen genomfördes i databaserna Pubmed och Cochrane. Studier som var randomiserade kontrollerade studier (RCT) alternativt cross-over studier inkluderades. Kvalitetsgranskning av studierna genomfördes med PEDro och tillförlitligheten av resultatet bedömdes med GRADEstud. Resultat: Åtta artiklar inkluderades, tre om biomekanik och fem om löpekonomi. Inga samstämmiga resultat sågs gällande barfotalöpningens effekter på GRF, en studie påvisade en signifikant minskning medan två studier visade på en signifikant ökning av GRF. Positiva tendenser sågs i studierna om löpekonomi, varav två påvisade signifikanta förbättringar. Kvaliteten på artiklarna bedömdes som måttlig och tillförlitligheten till resultaten bedömdes vara mycket låg.  Konklusion: Barfotalöpning påvisar vissa positiva effekter på löpekonomi medan effekterna på GRF är motstridiga. Tillförlitligheten av evidensen bedömdes vara mycket låg. Det behövs fler högkvalitativa studier som undersöker de långvariga och akuta effekterna av barfotalöpning på löpekonomi och biomekanik för att kunna dra slutsatser och implementera kunskapen bland fysioterapeuter som arbetar med löparskador. / Background: Running is a popular activity in Sweden today. However, injuries are common and almost 80% of runners get injured each year. Discussions about whether barefoot running could alter the biomechanics and decrease the risk of injury, and improve the running economy and increase a runner's performance, has risen amongst runners and researchers. Purpose: To examine the effects of barefoot running (minimalist footwear) on biomechanics measured with ground reaction force (GRF) and running economy measured with oxygen consumption compared to shod running.  Method: A systematic review. Articles were found using the Pubmed and Chochrane database. Randomised controlled trials (RCT) or Cross-over studies were included. Assessment of study quality was measured with the PEDro-scale and the reliability of the result assessed with GRADEstud. Result: Eight articles were included, three about biomechanics and five about running economy. Inconclusive results were found on the effects of barefoot running on GRF, one study showed a significant reduction in GRF and the other two showed increase in GRF. Positive tendencies were found concerning running economy, two studies showed a significant increase. The quality of the studies were moderate and the reliability of the result were very low. Conclusion: Barefoot running showed positive findings on running economy, while the effects on GRF were inconclusive. The evidence was considered very low. There is a need for more high-quality studies examining the long-lasting and acute effects of barefoot running on running economy and biomechanics to be able to draw conclusions and implement the knowledge in clinical physiotherapy.
864

Tåginducerade markvibrationer – analys med NGI:s verktyg VibTrain

Håård, Andreas January 2022 (has links)
Trafikverket, the Swedish Transport Administration, has been commissioned by the Swedishgovernment to make plans for new railway mainlines between the country’s three largest cities:Stockholm and Gothenburg/Malm¨o. The planned operating speed of the new mainlines isbetween 250–320 km/h. Train traffic at such high speeds across areas with soft soils may lead tolarge amplifications of the train induced ground vibrations, a phenomenon known as the groundvibration boom. The first observation of this phenomenon in practice occurred in Sweden in 1997,at the site Ledsg˚ard on the West Coast Line. This observation led to extensive investigationsand research. One of the research projects consisted of the development of the numerical calculationsoftware VibTrain by the Norwegian Geotechnical Institute, through which high speedtrain induced ground vibrations could be analyzed.The aim of this thesis has been to investigate whether VibTrain also could be used in planningworks for the new mainlines, specifically with respect to (i) evaluating the risk of the groundvibration boom and (ii) designing soil improvement measures. The investigation was conductedthrough calculations using the VibTrain software in three separate parts: (i) a verification of Vib-Train’s function on a modern computer by comparison with previous analyses for the Ledsg˚ardcase, (ii) a parametric study of the calculation model used in VibTrain and (iii) a comparison ofresults from VibTrain with results from the calculation software ωFE-N (¨Ulker-Kaustell 2016)for the location J¨arnasl¨atten in Ostl¨anken, a section of the new mainlines.The main findings from these calculations were:• The use of VibTrain on a modern computer worked well, and the verification of the program’sfunction through comparison with the Ledsg˚ard case yielded consistent results.• Modeling of soil improvement measures in the form of lime cement columns in VibTrain,using the method of equivalent modulus, gave results which principally agreed with theexpected behavior.• The comparison with results from the calculation software ωFE-N showed that the twoprograms agreed relatively well for a case with unimproved subgrade. In the analyzedcases with improved subgrade there were larger discrepancies, due to different modelingstrategies being used in the two programs.Based on the performed calculations, it is evident that VibTrain is best suited for initial assessmentsof the risk of the ground vibration boom. However, the calculation model is not sufficientlydetailed to be used in the design of soil improvement measures for the subgrade.
865

Use of Remote Sensing for Cover Type Interpretation Over the Ray Roberts Reservoir Area

Cassidy, Kelly Michela 12 1900 (has links)
As part of a pre-impoundment study for the Ray Roberts Reservoir Area, Landsat-5 multi-spectral scanner (MSS) imagery was used for cover type interpretation. This research was concerned with analysis techniques for MSS images and a comparison of results obtained using computer assisted interpretatin of MSS images and a comparison of results obtained using computer assisted interpretation of MSS images with those obtained using manual interpretation of false color infrared (CIR) photographs.
866

Jet/Wall Interaction: An Experimental Study with Applications to VSTOL Aircraft Ground Effects

El-Okda, Yasser Mohamed 07 May 2002 (has links)
The flow field of a twin jet impinging on ground plane with and without free-stream and at low jet-height-to-diameter ratios was investigated using the Particle Image Velocimetry (PIV) technique. Detailed, time-averaged flow field data are obtained via the high-resolution and the high-sampling rate instantaneous velocity field that is made available via the PIV technique. A model of twin jet issuing from 0.245m circular plate, with 0.019m jet exit diameter, and with jet span to diameter ratio of 3.0 is placed in a water tunnel with the jets in tandem arrangement with respect to the free-stream. The recently upgraded PIV system, in the ESM department fluid mechanics laboratory at VA-Tech, allowed us to capture instantaneous velocity field images of about 0.076m x 0.076m, at 512(H)x512(V) frame resolution. Sampling rates of 1000 and 1200 fps were employed. Understanding the flow field at lower heights is of crucial significance to the VSTOL aircraft application. Huge jet thrust is required to initiate the take-off operation due to the high lift loss encountered while the airframe is in proximity to the ground. Therefore, jet-height-to-diameter ratios of 2 and 4 were employed in this study. Jet-to-free-stream velocity ratios of 0.12, 0.18 and 0.22 were employed in addition to the no-free-stream case. In the current study, only time-averaged flow field properties were considered. These properties were extracted from the available instantaneous velocity field data. In order to provide some details in the time-averaged velocity field, the data were obtained along several planes of interrogation underneath the test model in the vicinity of the twin jet impinging flow. Images were captured in a single plane normal to the free-stream and five planes parallel to the free-stream. A vortex-like flow appears between the main jet and the fountain upwash. This flow is found to experience spiral motion. The direction of such flow spirals is found to be dependent on the jet exit height above the ground, and on the jet-to-free stream, velocity ratios. The flow spirals out towards the vortex flow periphery and upon increasing the free-stream it reverses its direction to be inward spiraling towards the core of the vortex. The flow reversal at certain height of the jet above the ground depends on the free-stream velocity. In our discussion, more emphasis is given to the case of jet-height-to-diameter ratio of two. We also found that the largest turbulent kinetic energy production rate is found to be at the fountain upwash formation zone. / Master of Science
867

Mobility Management and Localizability for Cellular Connected UAVs / Mobilitetshantering och Lokalisering för Mobilanslutna UAV:er

Meer, Irshad Ahmad January 2024 (has links)
Unmanned Aerial Vehicles (UAVs) connected to cellular networks present novel challenges and opportunities in mobility management and localization, distinct from those faced by terrestrial users. This thesis presents an integrated approach, combining two key aspects essential for the integration of UAVs with cellular networks. Firstly, it introduces the mobility management challenges for cellular-connected UAVs, which differ significantly from terrestrial users. While terrestrial mobility management primarily aims to prevent radio link failures near cell boundaries, aerial users experience fragmented and overlapping coverage with line-of-sight conditions involving multiple ground base stations (BSs). Thus, mobility management for UAVs extends beyond link failure avoidance, aiming to minimize unnecessary handovers while ensuring extended service availability, particularly in up-link communication. Line-of-sight conditions from a UAV to multiple BSs increase the likelihood of frequent handovers, resulting in control packet overheads and communication delays. This thesis proposes two approaches to address these challenges: 1) A model-based service availability-aware Mobility Robustness Optimization (MRO) adapting handover parameters to maintain high service availability with minimal handovers, and 2) A model-free approach using Deep Q-networks to decrease unnecessary handovers while preserving high service availability. Simulation results demonstrate that both the proposed algorithms converge promptly and increase the service availability by more than 40 %  while the number of handovers is reduced by more than 50%  as compared to traditional approaches. Secondly, to assess the ability of a network to support the range-based localization for cellular-connected UAVs, an analytical framework is introduced. The metric B-localizability is defined as the probability of successfully receiving localization signals above a specified Signal-to-Interference plus Noise Ratio (SINR) threshold from at least B ground BSs. The framework, accounting for UAV-related parameters in a three-dimensional environment, provides comprehensive insights into factors influencing localizability, such as distance distributions, path loss, interference, and received SINR. Simulation studies explore the correlation between localizability and the number of participating BSs, SINR requirements, air-to-ground channel characteristics, and network coordination. Additionally, an optimization problem is formulated to maximize localizability, investigating the impact of UAV altitude across different scenarios. Our study reveals that in an urban macro environment, the effectiveness of cellular network-based localization increases with altitude, with localizability reaching 100% above 60 meters. This finding indicates that utilizing cellular networks for UAV localization is a viable option. / Unmanned Aerial Vehicles (UAV) anslutna till cellulära nätverk presenterar nya utmaningar och möjligheter inom mobilitetshantering och lokalisering, skilda från dem som markanvändare står inför. Denna avhandling presenterar ett integrerat tillvägagångssätt, som kombinerar två nyckelaspekter som är väsentliga för integrationen av UAV:er med cellulära nätverk. För det första introducerar den mobilitetshanteringsutmaningarna för mobilanslutna UAV:er, som skiljer sig avsevärt från markbundna användare. Medan markbunden mobilitetshantering i första hand syftar till att förhindra radiolänkfel nära cellgränser, upplever antennanvändare fragmenterad och överlappande täckning med siktlinjeförhållanden som involverar flera markbasstationer (BS). Mobilitetshantering för UAV sträcker sig sålunda bortom att undvika länkfel, och syftar till att minimera onödiga överlämningar samtidigt som man säkerställer utökad servicetillgänglighet, särskilt i upplänkskommunikation. Synlinjeförhållanden från en UAV till flera BS:er ökar sannolikheten för frekventa överlämningar, vilket resulterar i kontrollpaketkostnader och kommunikationsförseningar. Denna avhandling föreslår två tillvägagångssätt för att möta dessa utmaningar: 1) En modellbaserad tjänsttillgänglighetsmedveten Mobility Robustness Optimization (MRO) som anpassar parametrar för överlämning för att bibehålla hög servicetillgänglighet med minimal överlämning, och 2) Ett modellfritt tillvägagångssätt med Deep Q- nätverk för att minska onödiga överlämningar samtidigt som hög servicetillgänglighet bibehålls. Simuleringsresultat visar att båda de föreslagna algoritmerna konvergerar snabbt och ökar tjänstens tillgänglighet med mer än 40% medan antalet överlämningar minskas med mer än 50% jämfört med traditionella metoder. För det andra, för att bedöma förmågan hos ett nätverk att stödja den räckviddsbaserade lokaliseringen för de cellulärt anslutna UAV:erna, introduceras ett analytiskt ramverk.Metriska B-lokaliseringsförmågan definieras som sannolikheten för att framgångsrikt ta emot lokaliseringssignaler över en specificerad signal-till-interferens plus brusförhållande (SINR) tröskel från minst B jord BSs.Ramverket, som tar hänsyn till UAV-relaterade parametrar i en tredimensionell miljö, ger omfattande insikter i faktorer som påverkar lokaliserbarhet, såsom avståndsfördelningar, vägförlust, störningar och mottagen SINR. Simuleringsstudier undersöker korrelationen mellan lokaliserbarhet och antalet deltagande BS:er, SINR-krav, luft-till-mark-kanalegenskaper och nätverkskoordination. Dessutom har ett optimeringsproblem formulerats för att maximera lokaliseringsförmågan, undersöka effekten av UAV-höjd över olika scenarier. Vår studie avslöjar att i en urban makromiljö ökar effektiviteten av mobilnätsbaserad lokalisering med höjden, med lokaliserbarhet som når 100% över $60$ meter. Detta fynd indikerar att användning av mobilnät för UAV-lokalisering är ett gångbart alternativ. / <p>QC 20240319</p>
868

GROUND WATER FLOW MODELING AND TRANSIENT PARTICLE TRACKING, APPLICATIONS FOR THE TRANSPORT OF <i>CRYPTOSPORIDIUM PARVUM</i> IN AN UNCONFINED BURIED BEDROCK VALLEY AQUIFER, SPRINGFIELD, OHIO

MERK, BRENDAN PAUL January 2005 (has links)
No description available.
869

White-ground lekythoi in context : An analysis of the geographical distribution, contexts, and value of white-ground lekythoi in the 5th century BCE

Eliasson, Carl William January 2022 (has links)
The aim of this study is to analyse and interpret the distribution of white-ground lekythoi with a known context from the 5th century BCE. Exploring white-ground lekythoi in context is a complex matter, as many lekythoi lack archaeological documentation. The purpose of this study is to locate and map white-ground lekythoi with available archaeological documentation in order to lay the groundwork of their geographical distribution and interpret how they were used and could have been viewed from a socio-economic perspective in different regions. The study has shown that white-ground lekythoi were distributed throughout the Mediterranean, the Black Sea and the Levant, and have been found in various contexts such as funerary, domestic and religious space depending on the region. The chronological distribution indicates that white-ground lekythoi were popular in locations such as Eretria, Gela and Macedonia, before becoming adopted in Attic funerary activities during the second half of the century. This suggests a more multifunctional use of the vessel than only being a funerary libation vessel which is the traditional scholarly approach to the vessel’s function. Lastly, this thesis addresses the value of white-ground lekythoi. The hypothesis is put forward that the vessels increased in value when being found in limited numbers and with what could be considered luxurious artefacts made for both a local and foreign market. / Målet med denna studie är att analysera och tolka fördelningen av vit-grundiga lekyter med en känd kontext från 500-talet f.v.t. Undersökningar av vit-grundiga lekyter med en känd kontext är en komplex fråga då många av kärlen saknar arkeologisk dokumentation. Syftet med studien är att lokalisera och kartlägga vit-grundiga lekyter med tillgänglig arkeologisk dokumentation för att lägga grunden för deras geografiska utspridning och tolka hur de användes och kunde ha blivit sedda från ett socio-ekonomiskt perspektiv i olika regioner. Studien har visat att vit-grundiga lekyter distribuerades över Medelhavet, Svarta havet och Levanten och har hittats i olika kontexter som gravar, bosättningar, och helgedomar beroende på region. Den kronologiska fördelningen indikerar att vit-grundiga lekyter var populära i områden som Eretria, Gela och Makedonien, innan de antogs i Attiska begravningsaktiviteter under andra hälften av seklet. Detta tyder på en mer multifunktionell användning av kärlen än enbart ämnat för begravningsaktiviteter som är den traditionella vetenskapliga tolkningen av kärlets funktion. Hypotesen framförs att vit-grundiga lekyter ökade i värde när de hittades i begränsat antal och tillsammans med vad man som kan betraktas som lyxiga artefakter gjorda för både en lokal och utländsk marknad.
870

Soil Genesis and Vegetation Response to Amendments and Microtopography in Two Virginia Coastal Plain Created Wetlands

Ott, Emily Thomas 12 June 2018 (has links)
Wetlands serve important ecosystem functions such as carbon sequestration but are often affected by disturbances like urban development, agriculture, and road building. For wetlands created to mitigate losses, it is important that the ecosystem functions successfully replicate those of natural wetlands. Created wetlands have frequently not provided these functions due to issues including low organic carbon (OC), high soil bulk density (BD), lost topsoil, incorrect hydrology, and failure of targeted vegetation establishment. Organic matter (OM) amendments help created wetlands attain these functions quicker, but, their long-term effects are seldom reported. This research's purpose was to measure the long-term effects of treatments at a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, non-tidal wetland created in 2002 (CCW). We tested OM treatments, topsoil amendment, and microtopography effects on soil and vegetation properties at WWE and OM treatments at CCW. Pedogenic changes in soil morphology, physical and chemical properties were detected by comparing data to previous studies at these sites. At both sites, litter and biomass parameters were measured to estimate total mass C. Herbaceous biomass was measured at WWE. At WWE, no long-term OM treatment effects from 78 or 156 Mg ha-1 were observed. Soils in pits had higher OC, lower BD, and lower chroma than soils on mounds. Sandy and loamy HSFI's developed at WWE within four years, but there were fewer sandy indicators after 12 years. Loamy HSFI's were lost at CCW from 2003 to 2016. Plots at WWE that were amended with topsoil had higher soil mass C than the sandy soil due to a finer texture, but total mass C did not vary. At CCW, long-term OM treatment effects were observed, including lower BD, higher soil mass C, and higher tree mass C with increasing compost rates up to 224 Mg ha-1. Overall, the ideal compost loading rate for constructed wetlands varied with wetland type and mitigation goals. Compost rates of 112 Mg ha-1 are sufficient for short term establishment of wetland vegetation and hydric soil properties, but higher rates near 224 Mg ha-1 may be required for effects that last over 10 years. / Ph. D.

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