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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.
71

Návrh nového kontinuálního systému měření jakosti páry / Proposal for a new system of continuous quality measurement pairs

Foltová, Anežka January 2016 (has links)
This paper deals with proposal of new continual system for quality measurement of sterilization steam. At the begining the process of sterilization is introduced. Then the concept of saturated streams, parameters for sterilization and sensors for measurement are described. Then the current process of measurement of steam quality is described and in the last part the proposal of the new system is introduced. After the draft was the measurement data, analysis and evalution.
72

nsAnalyser : Speech quality testing application for telephone service / nsAnalyser : Talkvalitetstestapplikation för telefonitjänst

Stahl, Alexander January 2013 (has links)
This degree project was made in collaboration with Nordicstation. The project task was to develop a testing application for a self-developed telephone survey service, which uses third party software. This third party software showed to be unreliable at higher loads. The purpose of the application is to analyse the speech quality of clients connected to the service. This report gives an introduction to the speech quality algorithms Perceptual Evaluation of Speech Quality (PESQ) and Single Sided Speech Quality Measure (3SQM). It also gives descriptions of the methods used to develop the application. The final chapters in this report are about the testing of the telephone service. The primary result of the testing was that the telephone service is unable to acceptably handle 80+ clients and recommendations to Nordicstation is to set a maximum of parallel connected clients to 80 or find an alternative to the third party software currently in use. / Detta examensarbete har gjorts i samarbete med Nordicstation. Projektets uppgift var att utveckla ett test program för at testa en egenutvecklad telefonundersökning-tjänst, baserad på tredjeparts mjukvara. Denna tredjeparts mjukvara visade sig vara opålitlig vid högre belastning. Syftet med programmet är att analysera samtals kvalitéten på de klienter som är anslutna till tjänsten. Denna rapport ger en introduktion till ljudkvalitetsalgoritmer så som Perceptual Evaluation of Speech Quality (PESQ) och Single Sided Speech Quality Measure (3SQM). Rapporten går även igenom de metoder som använts för att utvecklat programmet. De sista kapitlen i denna rapport är om själva testningen av telefonitjänsten. Det primära resultatet av testningen var att telefontjänsten inte kan hantera 80+ klienter acceptabelt och rekommendationer till Nordicstation är att sätta ett tak på maximalt parallellt anslutna klienter till 80 eller hitta ett alternativ till den tredjeparts mjukvara som nu används.
73

An Intelligent Multi Sensor System for a Human Activities Space---Aspects of Quality Measurement and Sensor Arrangement

Chen, Jiandan January 2011 (has links)
In our society with its aging population, the design and implementation of a highperformance distributed multi-sensor and information system for autonomous physical services become more and more important. In line with this, this thesis proposes an Intelligent Multi-Sensor System, IMSS, that surveys a human activities space to detect and identify a target for a specific service. The subject of this thesis covers three main aspects related to the set-up of an IMSS: an improved depth measurement and reconstruction method and its related uncertainty, a surveillance and tracking algorithm and finally a way to validate and evaluate the proposed methods and algorithms. The thesis discusses how a model of the depth spatial quantisation uncertainty can be implemented to optimize the configuration of a sensor system to capture information of the target objects and their environment with required specifications. The thesis introduces the dithering algorithm which significantly reduces the depth reconstruction uncertainty. Furthermore, the dithering algorithm is implemented on a sensor-shifted stereo camera, thus simplifying depth reconstruction without compromising the common stereo field of view. To track multiple targets continuously, the Gaussian Mixture Probability Hypothesis Density, GM-PHD, algorithm is implemented with the help of vision and Radio Frequency Identification, RFID, technologies. The performance of the tracking algorithm in a vision system is evaluated by a circular motion test signal. The thesis introduces constraints to the target space, the stereo pair characteristics and the depth reconstruction accuracy to optimize the vision system and to control the performance of surveillance and 3D reconstruction through integer linear programming. The human being within the activity space is modelled as a tetrahedron, and a field of view in spherical coordinates are used in the control algorithms. In order to integrate human behaviour and perception into a technical system, the proposed adaptive measurement method makes use of the Fuzzily Defined Variable, FDV. The FDV approach enables an estimation of the quality index based on qualitative and quantitative factors for image quality evaluation using a neural network. The thesis consists of two parts, where Part I gives an overview of the applied theory and research methods used, and Part II comprises the eight papers included in the thesis.
74

Development of a Procedure to Evaluate Groundwater Quality and Potential Sources of Contamination in the East Texas Basin

Alderman, John H. 05 1900 (has links)
This study contributes a procedure, based on data analysis and geostatistical methods, to evaluate the distribution of chemical ratios and differentiate natural and anthropogenic contaminant sources of groundwater quality in the East Texas Basin. Four aquifers were studied, Sparta, Queen City, Carrizo and Wilcox. In this study, Carrizo- Wilcox is considered as one aquifer, and Sparta-Queen City as another. These aquifers were divided into depth categories, 0-150 feet for Sparta-Queen City and 300-600 feet and 600-900 feet for Carrizo-Wilcox in order to identify individual sources of contamination. Natural sources include aquifer mineral make up, salt domes and lignite beds. Major anthropogenic sources include lignite and salt dome mining and oil-gas production. Chemical ratios selected were Na/Cl, Ca/Cl, Mg/Cl, SO4/Cl, (Na+Cl)/TDS, SO4/Ca and (Ca+Mg)/(Na+K). Ratio distributions and their relationships were examined to evaluate physical-chemical processes occurring in the study area. Potential contaminant sources were used to divide the Basin into three areas: Area 1 to the east, Area 2 in the west and Area 3 in the center. Bivariate analysis was used to uncover differences between the areas. The waters in Area 1 are potentially impacted primarily from oil field waters. Sources present in Area 2 include lignite beds and oil field operations. Area 3 is the cap rock of salt domes that can contain gypsum and anhydrite. Based on the exploratory data analysis (Na+Cl)/TDS, (Ca+Mg)/(Na+K), and SO4/Ca ratios were chosen for geostatistical analysis. Chemical ratios that provided indications of cation exchange, salt domes and oil fields were (Na+Cl)/TDS, (Ca+Mg)/(Na+K) and SO4/Ca. In the Sparta-Queen City 150 zone the procedure did not provide a good method for differentiating between contaminant sources. However, the procedure was effective to indicate impacted ground water in the Carrizo-Wilcox 600 and 900 foot zones.
75

Evaluation of the Chlorophyll/Fluorescence Sensor of the YSI Multiprobe: Comparison to an Acetone Extraction Procedure

Lambert, Patricia 05 1900 (has links)
The purpose of this study was to examine the suitability of the YSI model 6600 Environmental Monitoring System (multiprobe) for long term deployment at a site in Lewisville Lake, Texas. Specifically, agreement between a laboratory extraction procedure and the multiprobe chlorophyll/fluorescence readings was examined. Preliminary studies involved determining the best method for disrupting algal cells prior to analysis and examining the precision and linearity of the acetone extraction procedure. Cell disruption by mortar and pestle grinding was preferable to bath sonication. Comparison of the chlorophyll/fluorescence readings from the multiprobe and the extraction procedure indicated that they were significantly correlated but temperature dependent.
76

Storm Water System Monitoring for the Small Municipality Under Phase II of the National Pollutant Discharge Elimination System

Peacock, Steven 08 1900 (has links)
Storm water quality can have a significant impact on receiving water bodies. The chief recipients of these impacts are aquatic life in the receiving water body and downstream water users. Over the last few decades, legislation, regulations, institutions and facilities have evolved to recognize the impact of urban storm water on receiving streams. This increased emphasis has caused contaminants in storm water to be identified as a major concern. This developing concern has generated an increased interest in the water quality of our streams and lakes and emphasized the need for more monitoring efforts. With the passage of the National Pollutant Discharge Elimination System (NPDES) Phase II requirements, small municipalities are responsible for storm water impacts on receiving waters within their jurisdiction. For the purposes of NPDES Phase II requirements, small municipalities are identified as these municipalities that are typically composed of 10,000 but less than 100,000 in population. The purpose of this dissertation is to develop a manual for use by the staff of small municipalities in meeting the requirements prescribed by changes initiated in the NPDES Phase II regulations. Attempts were made to comply with these requirements within a very limited manpower and budget framework and to develop procedures that would allow for permit compliance using testing equipment that was both reliable and robust. The users' manual provides valuable guidance in the establishment of a knowledge base for characterization of the watersheds selected for study. Chapter 3 of the dissertation contains a users' manual, designed for use by municipal staff members in their efforts to comply with the NPDES Phase II requirements. Using the techniques and equipment capabilities developed during the writing of the users' manual a characterization of three watersheds within Denton County, Texas was developed. Non-storm water samples were taken from each of the streams and a baseline analysis was established. The three watersheds represented agricultural, suburban and urban settings. Storm water samples were obtained from multiple storms within all three watersheds and data analysis used to determine the character and impact of urban runoff. Determination of the constituents for analysis was based on monitoring requirements of the NPDES Phase I and II requirements for owners and operators of municipal separate storm sewer systems (MS4) and on the Texas Pollutant Discharge Elimination System (TPDES) Multi-Sector General Permit (MSGP). The three watersheds were determined to have multiple statistically significant differences for some parameters between their Base Flows and Storm Flows. The impact of urban runoff on the receiving waters of these three drainage systems was clearly demonstrated throughout the testing period.
77

Operating system based perceptual evaluation of call quality in radio telecommunications networks : development of call quality assessment at mobile terminals using the Symbian operating system, comparison with traditional approaches and proposals for a tariff regime relating call charging to perceived speech quality

Aburas, Akram January 2012 (has links)
Call quality has been crucial from the inception of telecommunication networks. Operators need to monitor call quality from the end-user's perspective, in order to retain subscribers and reduce subscriber 'churn'. Operators worry not only about call quality and interconnect revenue loss, but also about network connectivity issues in areas where mobile network gateways are prevalent. Bandwidth quality as experienced by the end-user is equally important in helping operators to reduce churn. The parameters that network operators use to improve call quality are mainly from the end-user's perspective. These parameters are usually ASR (answer seizure ratio), PDD (postdial delay), NER (network efficiency ratio), the number of calls for which these parameters have been analyzed and successful calls. Operators use these parameters to evaluate and optimize the network to meet their quality requirements. Analysis of speech quality is a major arena for research. Traditionally, users' perception of speech quality has been measured offline using subjective listening tests. Such tests are, however, slow, tedious and costly. An alternative method is therefore needed; one that can be automatically computed on the subscriber's handset, be available to the operator as well as to subscribers and, at the same time, provide results that are comparable with conventional subjective scores. QMeter® 'a set of tools for signal and bandwidth measurement that have been developed bearing in mind all the parameters that influence call and bandwidth quality experienced by the end-user' addresses these issues and, additionally, facilitates dynamic tariff propositions which enhance the credibility of the operator. This research focuses on call quality parameters from the end-user's perspective. The call parameters used in the research are signal strength, successful call rate, normal drop call rate, and hand-over drop rate. Signal strength is measured for every five milliseconds of an active call and average signal strength is calculated for each successful call. The successful call rate, normal drop rate and hand-over drop rate are used to achieve a measurement of the overall call quality. Call quality with respect to bundles of 10 calls is proposed. An attempt is made to visualize these parameters for better understanding of where the quality is bad, good and excellent. This will help operators, as well as user groups, to measure quality and coverage. Operators boast about their bandwidth but in reality, to know the locations where speed has to be improved, they need a tool that can effectively measure speed from the end-user's perspective. BM (bandwidth meter), a tool developed as a part of this research, measures the average speed of data sessions and stores the information for analysis at different locations. To address issues of quality in the subscriber segment, this research proposes the varying of tariffs based on call and bandwidth quality. Call charging based on call quality as perceived by the end-user is proposed, both to satisfy subscribers and help operators to improve customer satisfaction and increase average revenue per user. Tariff redemption procedures are put forward for bundles of 10 calls and 10 data sessions. In addition to the varying of tariffs, quality escalation processes are proposed. Deploying such tools on selected or random samples of users will result in substantial improvement in user loyalty which, in turn, will bring operational and economic advantages.
78

Implémentation d'algorithmes de reconnaissance biométrique par l'iris sur des architectures dédiées / Implementing biometric iris recognition algorithms on dedicated architectures

Hentati, Raïda 02 November 2013 (has links)
Dans cette thèse, nous avons adapté trois versions d'une chaine d'algorithmes de reconnaissance biométrique par l’iris appelés OSIRIS V2, V3, V4 qui correspondent à différentes implémentations de l’approche de J. Daugman pour les besoins d’une implémentation logicielle / matérielle. Les résultats expérimentaux sur la base de données ICE2005 montrent que OSIRIS_V4 est le système le plus fiable alors qu’OSIRIS_V2 est le plus rapide. Nous avons proposé une mesure de qualité de l’image segmentée pour optimiser en terme de compromis coût / performance un système de référence basé sur OSIRIS V2 et V4. Nous nous sommes ensuite intéressés à l’implémentation de ces algorithmes sur des plateformes reconfigurables. Les résultats expérimentaux montrent que l’implémentation matériel / logiciel est plus rapide que l’implémentation purement logicielle. Nous proposons aussi une nouvelle méthode pour le partitionnement matériel / logiciel de l’application. Nous avons utilisé la programmation linéaire pour trouver la partition optimale pour les différentes tâches prenant en compte les trois contraintes : la surface occupée, le temps d’exécution et la consommation d’énergie / In this thesis, we adapted three versions of a chain of algorithms for biometric iris recognition called OSIRIS V2, V3, V4, which correspond to different implementations of J. Daugman approach. The experimental results on the database ICE2005 show that OSIRIS_V4 is the most reliable when OSIRIS_V2 is the fastest. We proposed a measure of quality of the segmented image in order to optimize in terms of cost / performance compromise a reference system based on OSIRIS V2 and V4. We focused on the implementation of these algorithms on reconfigurable platforms. The experimental results show that the hardware / software implementation is faster than the software implementation. We propose a new method for partitioning hardware / software application. We used linear programming to find the optimal partition for different tasks taking into account the three constraints : the occupied area, execution time and energy consumption
79

An Investigation of Urban Mobile Source Aerosol Using Optical Properties Measured by CRDT/N: Diesel Particulate Matter and the Impact of Biodiesel

Wright, Monica Elizabeth 06 December 2012 (has links)
Mobile source emissions are a major contributor to global and local air pollution. Governments and regulatory agencies have been increasing the stringency of regulations in the transportation sector for the last ten years to help curb transportation sector air pollution. The need for regulations has been emphasized by scientific research on the impacts from ambient pollution, especially research on the effect of particulate matter on human health. The particulate emissions from diesel vehicles, diesel particulate matter (DPM) is considered a known or probable carcinogen in various countries and increased exposure to DPM is linked to increased cardiovascular health problems in humans. The toxicity of vehicle emissions and diesel particulate emissions in particular, in conjunction with an increased awareness of potential petroleum fuel shortages, international conflict over petroleum fuel sources and climate change science, have all contributed to the increase of biodiesel use as an additive to or replacement for petroleum fuel. The goal of this research is to determine how this increased use of biodiesel in the particular emission testing setup impacts urban air quality. To determine if biodiesel use contributes to a health or climate benefit, both the size range and general composition were investigated using a comprehensive comparison of the particulate component of the emissions in real time. The emissions from various biodiesel and diesel mixtures from a common diesel passenger vehicle were measured with a cavity ring-down transmissometer (CRDT) coupled with a condensation particle counter, a SMPS, a nephelometer, NOx, CO, CO2, and O3 measurements. From these data, key emission factors for several biodiesel and diesel fuel mixtures were developed. This approach reduces sampling artifacts and allows for the determination of optical properties, particle number concentration, and size distributions, along with several important gas phase species' concentrations. Findings indicate that biodiesel additions to diesel fuel do not necessarily have an air quality benefit for particulate emissions in this emission testing scenario. The often cited linear decrease in particulate emissions with increasing biodiesel content was not observed. Mixtures with half diesel and half biodiesel tended to have the highest particulate emissions in all size ranges. Mixtures with more than 50% biodiesel had slightly lower calculated mass for light absorbing carbon, but this reduction in mass is most likely a result of a shift in the size of the emission particles to a smaller size range, not a reduction in the total number of particles. Evaluation of the extensive optical properties from this experimental set-up indicates that biodiesel additions to diesel fuel has an impact on emission particle extinction in both visible and near-IR wavelengths. The B99 mixture had the smallest emission factor for extinction at 532 nm and at 1064 nm. For the extinction at 532 nm, the trend was not linear and the emission factor peaked at the B50 mixture. Results from intensive properties indicate that emissions from B5 and B25 mixtures have Ångström exponents close to 1, typical for black carbon emissions. The mixtures with a larger fraction of biodiesel have Ångström exponent values closer to 2, indicating more absorbing organic matter and/or smaller particle size in the emissions. Additional experimental testing should be completed to determine the application of these results and emission factors to other diesel vehicles or types of diesel and biodiesel fuel mixtures.
80

Modeling of Ultrafine Particle Emissions and Ambient Levels for the Near Roadside Environment

Ahmed, Sauda 03 April 2017 (has links)
Various epidemiological studies have linked exposure to Ultrafine Particles (UFP; diameter< 100 nm) to adverse health impacts. Roadway traffic is one of the major sources of UFPs and heavily influences UFP concentrations in the nearby vicinity of major roadways. Modeling efforts to predict UFPs have been limited due to the scarcity of reliable information on emissions, lack of monitoring data and limited understanding of complex processes affecting UFP concentrations near sources. In this study continuous measurement of ultrafine particle number concentrations (PNC) and mass concentrations of nitric oxide (NO), nitrogen dioxide (NO2) and PM2.5 was conducted near an arterial road and freeway at different seasons and meteorological conditions and integrated with traffic count data. PNC showed high correlation with NO (r=0.64 for arterial; 0.61 for freeway), NO2 (r=0.57 for arterial; 0.53 for freeway) and NOx (NOx=NO+NO2; r=0.63 for arterial; 0.59 for freeway) and moderate to low correlation with traffic volume (r=0.33 for arterial; 0.32 for freeway) and PM2.5 (r=0.28 for arterial; 0.23 for freeway); respectively; for both sites at 15 minute averages. The PNC-NOx relationship prevailed on a shorter term (15 min), hourly, and throughout the day basis. Both PNC and NOx showed comparatively higher correlation with traffic during the morning period but became lower during evening which can be attributed to the higher boundary layer and wind speeds. The variable meteorology in the evening affects both PNC and NOx concentrations in the same way and the correlation between NOx and PNC is maintained high both during morning (r=0.74 for arterial; 0.69 for freeway), and evening (r=0.62 for arterial; 0.59 for freeway) periods. Thus nitrogen oxides can be used as a proxy for traffic-related UFP number concentration reflecting the effect of both traffic intensity and meteorological dilution. The PNC-NOx relation was explored for various meteorological parameters i.e. wind speed and temperature. It is found that NOx emission is temperature independent and can be used to reflect the effect of traffic intensity and meteorological dilution. Once the effect of traffic intensity and dilution is removed, the effect of temperature on PNC-NOx ratio becomes important which can be attributed to the variation in PNC emission factors with temperature. The high morning PNC-NOx ratio found at the arterial road is a result of new particle formation due to lower temperature and low concentration of exhaust gases in the morning air favoring nucleation over condensation. This finding has important implication when calculating emission factors for UFP number concentrations. Thus it can be concluded that roadside concentration of ultrafine particles not only depends on traffic intensity but also on meteorological parameters affecting dilution or new particle formation. High concentrations of ultrafine particle number concentration close to a roadway is expected due to higher traffic intensity , as well as during low wind speed causing low dilution and low temperature conditions favoring new particle formation. Finally a simplified approach of calculating particle number emission factor was developed using existing and easily available emission inventory for traffic related tracer gases. Using NOx emission factors from MOVES emission model, the emission ratio of PNC to NOx was converted to develop particle number emission factors. NOx was selected as the traffic related tracer gas since the number concentration of particles is closely correlated to NOx, NOx and particles are diluted in the same way and NOx emission factors are available for a variety of traffic situations. To ensure contribution of fresh traffic exhaust, the average of the difference of pollutant concentrations at high traffic condition and background condition was used to calculate PNC-NOX ratio. Using nitrogen oxides to define background and high-traffic conditions and MOVES emission factor for NOX to convert corresponding PNC-NOX ratio, an average emission factor of (1.82 ± 0.17) E+ 14 particle/ vehicle-km was obtained, suitable for summertime. When compared to existing particle number emission factors derived from dynamometer tests, it was found that there exits reasonable agreement between the calculated real world particle number emission factors and emission factors from dynamometer tests. The calculated emission factor and R-Line dispersion model was tested in predicting near-road particle number concentrations. Although only 23% of the variability in PNC was explained by the dispersion model, 84.33% of the measurements fell within the factor of two envelope. This suggests that there is potential to effectively use these models and thus warrants more in-depth analysis. Finally, a simple map of PNC gradients from major roads of Portland was developed. The results of this study helped identify proxy-indicators to provide reference values for estimating UFP concentrations and emissions that can be used for simple evaluation of particle concentration near major roadways for environmental and urban planning purposes and to assess expected impact of UFP pollution on population living near roadways exposed to elevated concentrations.

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