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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.
221

Empirical Evaluation of Edge Computing for Smart Building Streaming IoT Applications

Ghaffar, Talha 13 March 2019 (has links)
Smart buildings are one of the most important emerging applications of Internet of Things (IoT). The astronomical growth in IoT devices, data generated from these devices and ubiquitous connectivity have given rise to a new computing paradigm, referred to as "Edge computing", which argues for data analysis to be performed at the "edge" of the IoT infrastructure, near the data source. The development of efficient Edge computing systems must be based on advanced understanding of performance benefits that Edge computing can offer. The goal of this work is to develop this understanding by examining the end-to-end latency and throughput performance characteristics of Smart building streaming IoT applications when deployed at the resource-constrained infrastructure Edge and to compare it against the performance that can be achieved by utilizing Cloud's data-center resources. This work also presents a real-time streaming application to detect and localize the footstep impacts generated by a building's occupant while walking. We characterize this application's performance for Edge and Cloud computing and utilize a hybrid scheme that (1) offers maximum of around 60% and 65% reduced latency compared to Edge and Cloud respectively for similar throughput performance and (2) enables processing of higher ingestion rates by eliminating network bottleneck. / Master of Science / Among the various emerging applications of Internet of Things (IoT) are Smart buildings, that allow us to monitor and manipulate various operating parameters of a building by instrumenting it with sensor and actuator devices (Things). These devices operate continuously and generate unbounded streams of data that needs to be processed at low latency. This data, until recently, has been processed by the IoT applications deployed in the Cloud at the cost of high network latency of accessing Cloud’s resources. However, the increasing availability of IoT devices, ubiquitous connectivity, and exponential growth in the volume of IoT data has given rise to a new computing paradigm, referred to as “Edge computing”. Edge computing argues that IoT data should be analyzed near its source (at the network’s Edge) in order to eliminate high latency of accessing Cloud for data processing. In order to develop efficient Edge computing systems, an in-depth understanding of the trade-offs involved in Edge and Cloud computing paradigms is required. In this work, we seek to understand these trade-offs and the potential benefits of Edge computing. We examine end to-end latency and throughput performance characteristics of Smart building streaming IoT applications by deploying them at the resource-constrained Edge and compare it against the performance that can be achieved by Cloud deployment. We also present a real-time streaming application to detect and localize the footstep impacts generated by a building’s occupant while walking. We characterize this application’s performance for Edge and Cloud computing and utilize a hybrid scheme that (1) offers maximum of around 60% and 65% reduced latency compared to Edge and Cloud respectively for similar throughput performance and (2) enables processing of higher ingestion rates by eliminating network bottleneck.
222

The Microbial Biochemical Potential of Two Detention-Retention Marshes in the Kissimmee River Valley Watershed

Winkelmann, Douglas A. 01 October 1981 (has links) (PDF)
One of the major programs to abate the deterioration of water quality in the Lake Okeechobee watershed was the addition of detention-retention facilities. The microbial biochemical potential of two different detention-retention marshes in the Kissimmee River Valley were examined to determine their effectiveness to improve water quality. The kinetics of decomposition and nutrient mineralization and assimilation, as mediated by microorganisms, and the enumeration of microorganisms capable of utilizing various substrates were studied. Various communities within each marsh were studied during a 2-year period. The decomposition rates of 3 plant substrates were determined. Chitin was used as a standard for organic decomposition. Chitin had significantly higher (p< 0.05) rates of decomposition than the plant material in all sites at both marshes. Chitin decomposition rates were significantly different (p< 0.05) between sites. Significant differences (p< 0.05) in rates of decomposition were also found between the 3 plant substrates. the difference in decomposition rates for the 3 plant substrates existed within sites, as well as between sites. The number of microorganisms and the mineralization and assimilation rates were significantly different (p< 0.05) between the detention-retention marshes. Significant differences (p< 0.05) in numbers of microorganisms and rates were also found between sites within each marsh. The variation in detrital processing demonstrated that site-specific dynamics occurred in the detention-retention marshes. Higher decomposition rates were associated with sediment sites containing organic matter with either a continuous, shallow flow of water or alternate wet/dry periods. Decomposition rates were lowest at sites containing sandy sediments, and dry soil sites without a flow of water. Higher aerobic and anaerobic bacterial activity was also associated with sediment sites containing organic matter with either a continuous, shallow flow of water are alternate wet/dry periods. Higher fungal activity was associated with alternate wet/dry sediment sites, but only during dry periods. Microbial activity was lowest at sites containing sandy sediments and in water columns.
223

A statistical approach to urban stormwater detention planning

Segarra, Rafael Ivan January 1988 (has links)
A statistical model has been developed to study the long-term behaviour of a stormwater detention unit. This unit stores a portion of the incoming runoff, corresponding to the empty space available in the unit, from which runoff is pumped to a treatment plant. The objective is to avoid, as much as possible, the discharge of untreated runoff to receiving bodies of water. The model was developed by considering the arrival of independent runoff events at the urban catchment. The process variables of event depth, duration, and interevent time were treated as independent, identically distributed random variables. A storage equation was formulated from which the probability of detention unit overflow was obtained. With this distribution it was possible to define the trap efficiency of the unit in terms of the long-term fraction of the runoff volume trapped by the storage unit. The trap efficiency expressions define storage/ treatment isoquants, which represent the combinations of storage capacity, treatment rate, and the sewer system runoff trapping capacity, which provide a fixed level of runoff control. A pollutant load model was also formulated, based on a first-order washoff model. This model was used to define pollutant control isoquants. Optimal values of the required storage capacity and treatment rate were obtained by treating the isoquants as production functions. Applying the results of production function theory, a cost minimization problem was solved for the value of the storage capacity and treatment rate, for prescribed runoff and pollutant trap efficiency levels. The results obtained with the statistical model compared well with results obtained from major simulation models. The statistical approach offers an advantage in that no simulation is required to obtain the isoquants, as the expressions are analytical, thus greatly simplifying the optimization process. Also, the evaluation of the storage unit pollutant trap efficiency can be easily evaluated for any type of pollutant whose washoff rate is known. / Ph. D.
224

Design of detention basin system along highways

Dhaubhadel, Manoranjan N. January 1983 (has links)
A system of detention basins is an effective device for control of, storm flood both in terms of quantity and quality. The feasibility of designing detention basins for flood control by use of abandoned spaces near highway interchange and between highway embankments is investigated. Three algorithms are examined for routing inflow hydrographs through interconnected basins under various hydraulic and. hydrologic conditions. The programs solve for both the time dependent flow quantities and the extent of pollutant removal in the system for given inflows and pollutant trap efficiencies of the individual basins. The first algorithm is the extended version of the classical single reservoir routing and involves solution of a system of simultaneous nonlinear equations. The other two algorithms employ the so-called linearized or simplified versions of the continuity equation. The algorithms can take care of various possible combinations of inflow, type of connections between basins, and the boundary conditions at the outlet(s). Results from the three algorithms are comparatively analysed and the one which does not require excessively small time step for solution convergence is selected. The Kuo method employing the standard approximation for the mass conservation equations as in classical single reservoir routing is found favorable with respect to the time step required for convergence and hence is selected for application to design examples. Various basin arrangements are included to show the routing results with respect to quantity and quality for different combinations of storm inflows and outlet structure types. Interconnection between basins is found desirable both in terms of quantity and quality control of effluent. / M.S.
225

Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering / Reduction of Pollutants in Storm Water Ponds : Governing Parameters and Methods for Statistical Modelling

Florberger, Jenny January 2006 (has links)
<p>Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.</p><p>This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined. The flow pattern was then simulated in four different storm water ponds, of varying shape and size, by using a physically based computer model. The residence time distribution for each pond could then be calculated as well as the hydraulic efficiency, which is a measure on how well the inflowing water is spread throughout a pond. Finally a multiple regression analysis was performed. This analysis examined how the reduction of lead, copper, zinc and cadmium depends on the following factors: the specific pond area, the variance of the residence time distribution, the hydraulic efficiency and the concentration of incoming metals and suspended solids. The specific pond area is a factor which is defined as the pond area divided by the reduced run off area.</p><p>The results from the multiple regression analysis indicate that an increasing content of inflowing suspended solids leads to a better treatment efficiency regarding lead and copper. The specific area showed to have some effect on the treatment efficiency, but this effect was less than that of the content of inflowing suspended solids. The reduction of cadmium depended mainly on the specific area and the incoming concentration of cadmium. An increasing reduction of zinc could to some extent be explained by an increasing specific area.</p><p>The results from this analysis and earlier studies are emphasizing the fact that adsorption to particles and sediment is one of the main processes for a good separation of heavy metals from storm water. Longer measurements series from additional treatment facilities are needed to build a statistical model which, in the future, can be used to predict the treatment efficiency of storm water ponds.</p> / <p>Dagvatten är regn- och smältvatten som samlas upp i avloppssystem. Då detta vatten huvudsakligen härstammar från urban bebyggelse så kan det innehålla höga halter tungmetaller, närsalter och olja med mera. Idag behandlas förorenat dagvatten bland annat genom nyttjande av dammar, våtmarker och översilningsytor. Dessa behandlingsalternativ har dock visat sig ge varierande resultat med avseende på dess reningseffektivitet.</p><p>Detta arbete har utförts på uppdrag av konsultföretaget SWECO VIAK och syftade till att studera vilka parametrar som påverkar reningseffekten av närsalter och tungmetaller i dagvattendammar. Genom litteraturstudier undersöktes de dominerande reningsprocesserna i dammar och våtmarker. Därefter modellerades strömningen i 4 dammar med varierande form och storlek. Vid detta arbete erhölls en fördelning av uppehållstiden hos vattnet för respektive damm samt ett värde på den hydrauliska effektiviteten, vilken är ett mått på hur väl det inströmmande vattnet sprids ut i dammen. Slutligen utfördes en multipel regressionsanalys.</p><p>Vid denna analys undersöktes hur reningen av bly, koppar, zink och kadmium beror av den specifika dammarean, variansen hos vattnets uppehållstidsfördelning, den hydrauliska effektiviteten samt inkommande metall- och TSS-koncentration (suspenderat material). Den specifika dammarean är en faktor vilken defineras som kvoten mellan dammens area och dess reducerade avrinningsområde.</p><p>Resultaten från den multipla regressionen tyder på att en ökad inkommande halt av suspenderat material till dammen har störst betydelse för en förbättrad avskiljning av bly och koppar. Även den specifika arean och metallkoncentrationen i inflödet visade sig ha en viss, men något mindre, betydelse. Reduktionen av kadmium berodde däremot till störst del av den specifika arean och inkommande kadmiumkoncentration. En ökad reduktion av zink förklarades till viss del av en ökad specifik area. Resultatet att halten av suspenderat material i hög grad avgör reningen samt tidigare studier understryker det faktum att adsorption till partiklar och sediment verkar vara en av de viktigaste processerna för en god avskiljning av tungmetaller. Längre mätserier från fler dagvattendammar krävs dock för att i framtiden ta fram en statistisk modell vilken skulle kunna användas till att prediktera reningseffekten.</p>
226

Automated dust storm detection using satellite images : development of a computer system for the detection of dust storms from MODIS satellite images and the creation of a new dust storm database

El-Ossta, Esam Elmehde Amar January 2013 (has links)
Dust storms are one of the natural hazards, which have increased in frequency in the recent years over Sahara desert, Australia, the Arabian Desert, Turkmenistan and northern China, which have worsened during the last decade. Dust storms increase air pollution, impact on urban areas and farms as well as affecting ground and air traffic. They cause damage to human health, reduce the temperature, cause damage to communication facilities, reduce visibility which delays both road and air traffic and impact on both urban and rural areas. Thus, it is important to know the causation, movement and radiation effects of dust storms. The monitoring and forecasting of dust storms is increasing in order to help governments reduce the negative impact of these storms. Satellite remote sensing is the most common method but its use over sandy ground is still limited as the two share similar characteristics. However, satellite remote sensing using true-colour images or estimates of aerosol optical thickness (AOT) and algorithms such as the deep blue algorithm have limitations for identifying dust storms. Many researchers have studied the detection of dust storms during daytime in a number of different regions of the world including China, Australia, America, and North Africa using a variety of satellite data but fewer studies have focused on detecting dust storms at night. The key elements of this present study are to use data from the Moderate Resolution Imaging Spectroradiometers on the Terra and Aqua satellites to develop more effective automated method for detecting dust storms during both day and night and generate a MODIS dust storm database.
227

Synthesis and characterisation of peptide-based probes for quantitative multicolour STORM imaging

Taylor, Edward John Robert January 2018 (has links)
Current single molecule localisation microscopy methods allow for multicolour imaging of macromolecules in cells, and for a degree quantification on molecule numbers in one colour. However, that has not yet been an attempt to develop tools capable of quantitative imaging with multiple colours in cells. This work addressed this challenge by designing linker peptides with chemospecific groups to allow attachment of activator and emitter dyes for STORM imaging, and a targeting module. The design ensured a stoichiometric ratio of targeting module to activator and emitter dyes. Peptides with HaloTag ligands attached were labelled with various activator and emitter pairs and used to label HaloTag fusions of S. pombe and mouse embryonic stem cells. These peptides were found to bind non-specifically to various areas of both cell types, and did not localise to HaloTag protein, whereas controls did. Another peptide was also labelled with activator-emitter pairs and attached to expressed anti-GFP and ant-mCherry nanobodies via native chemical ligation. The labelled anti-GFP nanobody was to demonstrate ensemble and single molecule imaging in S. pombe, as well as characterisation on single molecule surfaces in comparison to a conventional randomly labelled antibody. The stoichiometrically labelled nanobody had a more consistent number of photons detected per localisation, number of localisation per molecule and number of blinks per molecule, which implied that it could be more useful than randomly labelled nanobodies for counting experiments. It was also shown to be capable of specific laser activation for STORM imaging with both an Alexa405Cy5 and Cy3Cy5 pairs. These anti-GFP and anti-mCherry nanobodies and peptide linker are new tools for both counting and multicolour imaging in super-resolution, which could be widely applied to constructs that are already tagged with GFP or mCherry.
228

Sedimentological Characteristics and 3-D Internal Architecture of Washover Deposits from Hurricanes Frances, Ivan, and Jeanne

Horwitz, Mark H 13 November 2008 (has links)
Extensive overwash occurred along Florida's Atlantic and northern Gulf facing barrier islands during the passages of Hurricanes Frances, Ivan, and Jeanne in 2004. These high-energy storm events provided a unique opportunity to study the spatial depositional patterns and internal sedimentary architecture of fresh washover deposits resulting from inundation to collision regime overwash events. Sedimentological characteristics and 3-D internal architecture of the washover deposits were studied through coring, trenching, sediment analysis, ground penetrating radar (GPR) surveys, and pre- and post-storm aerial photography and LiDAR topographic survey data. The cross-shore extent of washover deposition is controlled by sediment supply, accommodation space, and the extent of cross-shore penetration of overwash flow. Antecedent morphology of the beach or barrier island is the primary factor governing sediment supply and accommodation space. Antecedent morphology coupled with spatio-temporal factors including storm position, intensity, and duration govern the extent of landward excursion of overwash flow. Washover deposition ranges from thin deposits, limited in cross-shore extent to the beach berm, to extensive sheet-like sediment bodies extending across an entire barrier island profile. Four sedimentary facies are recognized, which can be related to antecedent morphology. Berm facies, dominates the beach and seaward side of the foredune, and is characterized by a basal erosional surface and seaward dipping planar stratification. Back-berm facies extends landward from the dune crest down the backside of the foredune, exhibits little evidence of erosion along the basal contact, and is dominated by landward inclined stratification. Platform facies, largely confined to the interior platform, exhibits little evidence of erosion along the pre-storm surface, and horizontal to gently landward dipping parallel stratification, which merges landward with, and commonly overlies steeply landward dipping foreset stratification. Antecedent hummocky dunes may be preserved within platform facies. The landward most facies, backbay facies is dominated by subaqueous deposition within the back bay, and is characterized by steeply landward dipping tabular foreset and sigmoidal stratification. In the longshore direction, backbay facies exhibit trough and mound GPR reflective patterns, representing washover sediment ridges and troughs oriented parallel to the primary flow direction, and illustrate the highly 3-dimesional nature of the washover deposits.
229

Manöverkrigföring : en stagnerad eller utvecklad teori?

Edberg, Johan January 2009 (has links)
<p>Manöverkrigföring är ett vedertaget begrepp inom militär teori. Jag har i denna uppsats valt att analysera och jämföra två operationer som baseras på manöverkrigföring.</p><p>Vid Tysklands invasion av Frankrike 1940, Fall Gelb, utgjorde manöverteorin grunden för operationen. Detta var första gången som manöverkrigföring utnyttjades i stor skala för att slå en jämbördig motståndare.</p><p> I den USA-ledda FN-koalitionens invasion av Irak 1991, Desert Storm, var manöverkrigföring ännu en gång den operativa huvudteorin i planerna för operationen.</p><p>Den här uppsatsen är en komparativ fallstudie baserad på kvalitativ textanalys. Båda operationerna beskrivs för att sedan jämföras varvid skillnader och likheter belyses.</p><p>Resultatet visar att såväl Fall Gelb som Desert Storm genomfördes som operationer baserade på teorin om manöverkrigföring, men att stora skillnader finns mellan dessa operationer. Orsaken till skillnaderna belyses till del och vissa teorier om vad dessa beror på presenteras.</p> / <p>Maneuver warfare is a widely accepted term used in military theory. I have in this essay chosen to analyse and compare two operations that were based on maneuver warfare.</p><p>In Germany’s invasion of France in 1940, Fall Gelb, maneuver theory was used as a base for the operation. It was the first time maneuver warfare was used in large scale to defeat an equal opponent.</p><p>In the US led UN-coalitions invasion of Iraq in 1991, Desert Storm, maneuver warfare was once again the cornerstone in the planning of the operation.</p><p> This essay is a comparative study based on qualitative text-analysis. Both operations are first described and then compared to one and other, and differences and similarities are shown.</p><p>The results show that both Fall Gelb and Desert Storm were fought based on the theory of maneuver warfare, but that large differences exist between the two operations. The reasons for these differences are not shown in detail, but some theories are presented.</p>
230

Manöverkrigföring : en stagnerad eller utvecklad teori?

Edberg, Johan January 2009 (has links)
Manöverkrigföring är ett vedertaget begrepp inom militär teori. Jag har i denna uppsats valt att analysera och jämföra två operationer som baseras på manöverkrigföring. Vid Tysklands invasion av Frankrike 1940, Fall Gelb, utgjorde manöverteorin grunden för operationen. Detta var första gången som manöverkrigföring utnyttjades i stor skala för att slå en jämbördig motståndare.  I den USA-ledda FN-koalitionens invasion av Irak 1991, Desert Storm, var manöverkrigföring ännu en gång den operativa huvudteorin i planerna för operationen. Den här uppsatsen är en komparativ fallstudie baserad på kvalitativ textanalys. Båda operationerna beskrivs för att sedan jämföras varvid skillnader och likheter belyses. Resultatet visar att såväl Fall Gelb som Desert Storm genomfördes som operationer baserade på teorin om manöverkrigföring, men att stora skillnader finns mellan dessa operationer. Orsaken till skillnaderna belyses till del och vissa teorier om vad dessa beror på presenteras. / Maneuver warfare is a widely accepted term used in military theory. I have in this essay chosen to analyse and compare two operations that were based on maneuver warfare. In Germany’s invasion of France in 1940, Fall Gelb, maneuver theory was used as a base for the operation. It was the first time maneuver warfare was used in large scale to defeat an equal opponent. In the US led UN-coalitions invasion of Iraq in 1991, Desert Storm, maneuver warfare was once again the cornerstone in the planning of the operation.  This essay is a comparative study based on qualitative text-analysis. Both operations are first described and then compared to one and other, and differences and similarities are shown. The results show that both Fall Gelb and Desert Storm were fought based on the theory of maneuver warfare, but that large differences exist between the two operations. The reasons for these differences are not shown in detail, but some theories are presented.

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