Falls and their consequences are a major health problem in the older population, increasing their immobility, morbidity and mortality. This thesis focuses on older people living in geriatric care settings, frail older people who are most prone to suffer falls. The aim was to study predisposing and precipitating factors associated with falls in older people with or without cognitive impairment. In a cross-sectional study with a one-year prospective follow-up for falls 63% of the 83 residents suffered 163 falls and 65% of the fallers fell more than once. The antidepressants selective serotonine reuptake inhibitors (SSRIs), impaired vision and being unable to use stairs independently were the factors most strongly associated with sustaining falls. Acute diseases were judged to have precipitated 32 % of the falls and drug side effects 9%. In another cross-sectional study with a one-year follow-up for falls, including 199 residents, previous falls and treatment with antidepressants (mainly SSRIs) were found to be the most important predisposing factor for falls. Acute disease was judged to be the precipitating factor alone or in combination, in 39% of the falls, medical drugs in 8%, external factors such as obstacles in 8% and other conditions both related to the individual and the environment, such as misinterpretation, misuse of roller walkers or mistakes made by the staff were judged to have precipitated 17% of the falls. In a population-based cross-sectional study including 3604 residents in geriatric care settings more than 8% sustained a fall at least once during the preceding week. A history of falls, the ability to get up from a chair, the need for a helper when walking, pain, cognitive impairment, use of neuroleptics and use of antidepressants were all associated with falls in multivariate analyses. In the subgroup of people with cognitive impairment (2008 residents) more than 9% had sustained a fall at least once during the preceding week. As for the whole population, being able to get up from a chair, previous falls, needing a helper when walking with the addition of hyperactive symptoms were the factors independently associated with falls. In a study with a one-year prospective follow up for falls, including 439 residents in residential care facilities, 63% sustained 1354 falls, corresponding to an incidence rate of 3.5 falls / person year. Thirty-three percent of the falls and 37% of the injurious falls occurred during the night (9pm-6am). There were significantly higher fall rates in the evening and in January, April, May, November and December. There were no associations between fall rates and any of the weather parameters studied. In conclusion falls and fall-related injuries in older people in geriatric care settings are common. Both predisposing and precipitating factors contribute to the risk of falling. Addressing precipitating factors for falls seems to be important in an individualised preventive strategy among older people in geriatric care settings.

A series of land-use-land-cover-change (LULCC) based sensitivity experiments, including changes in vegetation type, fractional vegetation (FV), and soil moisture (SM), over Western Kentucky were conducted to investigate atmospheric response to land-use. The choice of land-use for this study was chosen in the context of Western Kentucky’s historical LULCC. For this study, vegetation types considered were grassland, forest, and bare soil with further variations in FV for grassland and forest at 25, 50, 75, and 100 % and systematic increases and decreases in volumetric SM of 0.05, 0.10, and 0.15 m3 m-3. To the author’s knowledge, this is the first assessment of its kind that incorporates these types of LULCC in a single study. In addition, typical anthropogenic land-use change often incorporates several types of LULCC. Moreover, this assessment provides a robust analysis of the impacts LULCC has on atmospheric processes over Western Kentucky. To simulate the importance of land-use on atmospheric processes, a well known meso-scale model developed by the National Center for Atmospheric Research (NCAR) and the Pennsylvania State University (PSU) MM5 coupled with an intermediately complex land surface model (LSM) Noah was used. The purpose of this research is to investigate the impact of multiple types of LULCC on planetary boundary layer (PBL) evolution, PBL stability, near surface 3D-wind fields, temperature, and moisture. Furthermore, it is anticipated that multiple types of LULCC will provide more insight into the complex nonlinear land-atmosphere interactions from atmospheric, air quality, and climatology perspectives. Modeling analysis revealed the importance of land-use on atmospheric processes. Changes in all three types of LULCC (land-cover, FV, and SM) altered the distribution of surface energy and moisture, PBL structure, 3D-wind fields, and PBL stability. In general, it was found that LULCC that enhanced (diminished) ET rates reduced (increased) sensible heat flux, atmospheric temperature and, and PBL heights below (above) control (CTRL). For instance, the conversion of land-cover from CTRL to grassland reduced 2 m temperature and PBL heights by 0.60 °C and 228 m respectively compared to CTRL due to an evaporative advantage (lower stomata resistance). Multiple types of land-use change were found to either offset or enhance overall modeled response to LULCC. A reduction in FV to 25 % over grassland diminished ET despite the evaporation advantage of grassland and increased 2 m temperature and PBL heights with respect to CTRL by 3.3 °C and 504 m. These results significantly altered horizontal and vertical wind fields, affecting moisture advection and the development of meso-scale circulations. Compared to CTRL, these differences were enhanced over drier soils, but muted over moist soils. Moreover, the impact of LULCC on atmosphere evolution was not only dependent on the type of LULCC, but also on the current state of other unaltered land surface features such as vegetation type, FV, and SM. Alterations to modeled PBL development, as a result of LULCC, can have important impacts on a region’s climatology and air quality. Simulated changes in typical PBL moisture and temperature through time can affect local and regional climatology. Depending on the type of LULCC, these alterations in climate may lead to localized cooling. In addition, it was further hypothesized that changes in PBL height can affect air quality. Given the capping inversion layer at the top of the PBL, changes in PBL heights can significantly affect air quality with lower (higher) PBL heights diminishing (enhancing) air quality. Moreover, this research prescribes the importance of considering LULCC in atmospheric assessments of climatology and air quality, including pollutant dispersion and trajectory modeling.

Modeling spatiotemporal data, in particular fuzzy and complex spatial objects representing geographic entities and relations, is a topic of great importance in geographic information systems, computer vision, environmental data management systems, etc. Because of complex requirements, it is challenging to design a database for spatiotemporal data and its features and to effectively query them. This thesis presents a new approach for modeling, indexing and querying the spatiotemporal data of fuzzy spatial and complex objects and/or spatial relations. As a case study, we model and implement a meteorological application in an intelligent database architecture, which combines an object-oriented database with a knowledge base.

Weather is a major contributing factor in aviation accidents, incidents and delays. Doppler weather radar has emerged as a potent tool to observe weather. Aircraft carry an onboard radar but its range and angular resolution are limited. Networks of ground-based weather radars provide extensive coverage of weather over large geographic regions. It would be helpful if these data can be transmitted to the pilot. However, these data are highly voluminous and the bandwidth of the ground-air communication links is limited and expensive. Hence, these data have to be compressed to an extent where they are suitable for transmission over low-bandwidth links. Several methods have been developed to compress pictorial data. General-purpose schemes do not take into account the nature of data and hence do not yield high compression ratios. A scheme for extreme compression of weather radar data is developed in this thesis that does not significantly degrade the meteorological information contained in these data. The method is based on contour encoding. It approximates a contour by a set of systematically chosen ‘control’ points that preserve its fine structure upto a certain level. The contours may be obtained using a thresholding process based on NWS or custom reflectivity levels. This process may result in region and hole contours, enclosing ‘high’ or ‘low’ areas, which may be nested. A tag bit is used to label region and hole contours. The control point extraction method first obtains a smoothed reference contour by averaging the original contour. Then the points on the original contour with maximum deviation from the smoothed contour between the crossings of these contours are identified and are designated as control points. Additional control points are added midway between the control point and the crossing points on either side of it, if the length of the segment between the crossing points exceeds a certain length. The control points, referenced with respect to the top-left corner of each contour for compact quantification, are transmitted to the receiving end. The contour is retrieved from the control points at the receiving end using spline interpolation. The region and hole contours are identified using the tag bit. The pixels between the region and hole contours at a given threshold level are filled using the color corresponding to it. This method is repeated till all the contours for a given threshold level are exhausted, and the process is carried out for all other thresholds, thereby resulting in a composite picture of the reconstructed field. Extensive studies have been conducted by using metrics such as compression ratio, fidelity of reconstruction and visual perception. In particular the effect of the smoothing factor, the choice of the degree of spline interpolation and the choice of thresholds are studied. It has been shown that a smoothing percentage of about 10% is optimal for most data. A degree 2 of spline interpolation is found to be best suited for smooth contour reconstruction. Augmenting NWS thresholds has resulted in improved visual perception, but at the expense of a decrease in the compression ratio. Two enhancements to the basic method that include adjustments to the control points to achieve better reconstruction and bit manipulations on the control points to obtain higher compression are proposed. The spline interpolation inherently tends to move the reconstructed contour away from the control points. This has been somewhat compensated by stretching the control points away from the smoothed reference contour. The amount and direction of stretch are optimized with respect to actual data fields to yield better reconstruction. In the bit manipulation study, the effects of discarding the least significant bits of the control point addresses are analyzed in detail. Simple bit truncation introduces a bias in the contour description and reconstruction, which is removed to a great extent by employing a bias compensation mechanism. The results obtained are compared with other methods devised for encoding weather radar contours.

The analysis of heterogeneous, complex data sets has become important in many scientific domains. With the help of scientific visualization, researchers can be supported in exploring their research results. One domain, where researchers have to deal with spatio-temporal data from different sources including simulation, observation and time-independent data, is meteorology. In this thesis, a concept and workflow for the 3D visualization of meteorological data was developed in cooperation with domain experts. Three case studies have been conducted based on the developed concept. In addition, the concept has been enhanced based on the experiences gained from the case studies. In contrast to existing all-in-one software applications, the proposed workflow employs a combination of existing software applications and their extensions to make a variety of already implemented visualization algorithms available. The workflow provides methods for data integration and for abstraction of the data as well as for generating representations of the variables of interest. Solutions for visualizing sets of variables, comparing results of multiple simulation runs and results of simulations based on different models are presented. The concept includes the presentation of the visualization scenes in virtual reality environments for a more comprehensible display of multifaceted data. To enable the user to navigate within the scenes, some interaction functionality was provided to control time, camera, and display of objects. The proposed methods have been selected with respect to the requirements defined in cooperation with the domain experts and have been verified with user tests. The developed visualization methods are used to analyze and present recent research results as well as for educational purposes. As the proposed approach uses generally applicable concepts, it can also be applied for the analysis of scientific data from other disciplines. / In nahezu allen Wissenschaftsdisziplinen steigt der Umfang erhobener Daten. Diese sind oftmals heterogen und besitzen eine komplexe Struktur, was ihre Analyse zu einer Herausforderung macht. Die wissenschaftliche Visualisierung bietet hier Möglichkeiten, Wissenschaftler bei der Untersuchung ihrer Forschungsergebnisse zu unterstützen. Eine der Disziplinen, in denen räumlich-zeitliche Daten aus verschiedenen Quellen inklusive Simulations- und Observationsdaten eine Rolle spielen, ist die Meteorologie. In dieser Arbeit wurde in Zusammenarbeit mit Experten der Meteorologie ein Konzept und ein Workflow für die 3D-Visualisierung meteorologischer Daten entwickelt. Dabei wurden drei Fallstudien erarbeitet, die zum einen auf dem erstellten Konzept beruhen und zum anderen durch die während der Fallstudie gesammelten Erfahrungen das Konzept erweiterten. Der Workflow besteht aus einer Kombination existierender Software sowie Erweiterungen dieser. Damit wurden Funktionen zur Verfügung gestellt, die bei anderen Lösungsansätzen in diesem Bereich, die oft nur eine geringere Anzahl an Funktionalität bieten, nicht zur Verfügung stehen. Der Workflow beinhaltet Methoden zur Datenintegration sowie für die Abstraktion und Darstellung der Daten. Es wurden Lösungen für die Visualisierung einer Vielzahl an Variablen sowie zur vergleichenden Darstellung verschiedener Simulationsläufe und Simulationen verschiedener Modelle präsentiert. Die generierten Visualisierungsszenen wurden mit Hilfe von 3D-Geräten, beispielsweise eine Virtual-Reality-Umgebung, dargestellt. Die stereoskopische Projektion bietet dabei die Möglichkeit, diese komplexen Daten mit verbessertem räumlichem Eindruck darzustellen. Um dem Nutzer eine umfassende Analyse der Daten zu ermöglichen, wurden eine Reihe von Funktionen zur Interaktion zur Verfügung gestellt, um beispielsweise Zeit, Kamera und die Anzeige von 3D-Objekten zu steuern. Das Konzept und der Workflow wurden entsprechend der Anforderungen entwickelt, die zusammen mit Fachexperten definiert wurden. Des Weiteren wurden die Anwendungen in verschiedenen Entwicklungsstadien durch Nutzer getestet und deren Feedback in die Entwicklung einbezogen. Die Ergebnisse der Fallstudien wurden von den Wissenschaftlern benutzt, um ihre Daten zu analysieren, sowie diese zu präsentieren und in der Lehre einzusetzen. Da der vorgeschlagene Workflow allgemein anwendbare Konzepte beinhaltet, kann dieser auch für die Analyse wissenschaftlicher Daten anderer Disziplinen verwendet werden.

Dažniausiai inversijos sąlygos pavojingos miestams/ didmiesčiams, kurių didžiausias teršalų kiekis išmetamas dienos metu, o naktį teršalams išsisklaidyti trukdo inversijos reiškinys, kuris išsilaiko iki paryčių. Todėl yra svarbu kuo aiškiau apibrėžti inversijos sąlygų susidarymo priežastis ir išanalizuoti šio reiškinio įtaką miesto taršai. Taigi šіo dаrbo tіkѕlаѕ – nuѕtаtytі temperаtūroѕ іnverѕіјoѕ dėѕnіngumų įtаkа oro teršаlų ѕklаіdаі Kаuno mіeѕte. Pagrindiniai uždaviniai: nuѕtаtytі temperаtūroѕ іnverѕіјoѕ dėѕnіngumą pаroјe ѕkіrtіngаіѕ metų lаіkаіѕ, tuomet іšаnаlіzuotі temperаtūroѕ іnverѕіјoѕ įtаką teršаlų koncentrаcіјаі іr ѕtаtіѕtіškаі įvertіntі ryšіnę prіklаuѕomybę tаrp šіų rodiklių, taip pat įvertіntі kіtų meteorologіnіų rodiklių įtаką temperаtūroѕ іnverѕіјoѕ formаvіmuіѕі beі teršаlų pаѕіѕkіrѕtymuі kartu įvertinant oro teršalų koncentracijų ribinių verčių dinamiką 2006-2008 metais. Pagrindinis darbo metodas - duomenų analizė ir jų statistinių sąryšių kiekybinis įvertinimas. Atlikus tyrimą paaiškėjo kad, naktinės temperаtūroѕ іnverѕіјoѕ reіškіnyѕ Kаuno mіeѕte pаѕіreіškіа bet kurіuo metų lаіku іr ѕkіrіаѕі tіk vertіkаlаuѕ temperаtūroѕ grаdіento аmplіtudė. Taip pat nustatytos teigiamos vidutinio stiprumo teršalų koncentracijos priklausomybės nuo temperatūros inversijos išskyrus SO2. Be to nustatyta, kad KD10 koncentracija 2006 -2008 metų kovo pabaigoje ir balandžio pradžioje pasiekia didžiausią lygį ir viršija leistiną paros koncentracijos vertę, kai NO2 koncentracija ore... [toliau žr. visą tekstą] / Most inversion conditions dangerous cities / cities with the highest emissions of pollutants during the day and night to disperse pollutants prevents inversion phenomenon, which exists to morning. It is important to clarify the reasons for the formation of inversion conditions and analyze the impact of the phenomenon of urban pollution. The main thesis goal is to identify temperature inversions conditions and its impaction to the spread of pollutant Main tasks: identify temperature inversion phenomenon in different cycles of year, then calculate temperature inversion and pollutants correlation plus to analyze the concentration amount of pollutants in 2006- 2008 years. The method used for this investigation is the analysis of the data correlations calculation. The investigation revealed that temperature inversion exist on all cycles of year and detectable on night. Also the positive dependence of pollutant concentration to temperature inversion is detected, with the exception of SO2. In addition, it was found that the concentration of KD10 exceeded maximum values on 2006 -2008 in the end of March and beginning of April. What is more, NO2 concentration in air exceeds its level a several times a year and this is the signal for our health.

Šiame magistro baigiamajame darbe ištirta ir įvertinta Lietuvos hidrometeorologijos tarnybos teikiamų paslaugų efektyvumas, kokybė, vertinimas bei tobulinimo galimybės, iškeltos paslaugų kokybės vertinimo problemos bei pateikti pasiūlymai šių problemų sprendimui. Pirmoje dalyje tiriamos paslaugų sampratos, paslaugų ypatumai, vieša ir meteorologijos paslauga bei vartotojų pasitenkinimo indeksas. Išanalizuoti šeši pagrindiniai paslaugų kokybės modeliai. Antroje dalyje pateikta tyrimų metodologija. Aprašytas instrumentarijus dviejų atliktų tyrimų. Pirmasis tyrimas - hidrometeorologijos tarnybos vieša vartotojų pasitenkinimo apklausa atlikta tarnybos tinklalapyje. Antrasis tyrimas - hidrometeorologijos tarnybos paslaugų kokybės vertinimas, paslaugų vartotojų anketavimo būdas. Trečiojoje dalyje aprašoma hidrometeorologijos tarnybos charakteristika, atliktų tyrimų rezultatai. Aptartos tobulinimo galimybės. Pateikiami paslaugų kokybės gerinimo būdai. / This master's thesis investigates and assesses the efficiency of services, services‘ quality, assessment and improvement opportunities, raises the problems of services‘ quality and provide suggestions for solving these problems in Lithuanian Hydrometeorological Service. The first part explores the concept of services, services’ features, public meteorological service and customer satisfaction index. There are analyzed six main service quality models. The second part is intended to explain the methodology. There are described two instrumentations used for analysis. The first analysis aims to investigate public users’ satisfaction with Hydrometeorological Service and was implemented in the Authority's website. The second analysis covers Hydrometeorological Service services’ quality assessment and was implemented by questioning service’ customers. The third part describes basic characteristics of Hydrometeorological Service and examines research results. There are possibilities for improvements discussed and methods how to improve the quality of services explained.

Baigiamajame darbe pateikiami lauko eksperimento, vykdyto Aleksandro Stulginskio universiteto bandymų stotyje 2010–2011 m., duomenys. Dirvožemis karbonatingas sekliai glėjiškas išplautžemis (Calc(ar)i-Epihypogleyic Luvisol). Tyrimo tikslas – įvertinti sėjos laiko įtaką linijinių ir hibridinių žieminių rapsų derliaus formavimuisi skirtingos trukmės šiltėjančiu rudens – žiemos periodu. Sėjos laikas ir veislė turėjo esminės įtakos žieminių rapsų pasėlių tankumui rudenį. Rugpjūčio 20 d., rugsėjo 5 ir 10 d. sėtų skirtingų veislių žieminių rapsų pasėlių tankumas skyrėsi esmingai – tankesni buvo linijinės veislės rapsų pasėliai. Žieminių rapsų sudygimui įtakos turėjo meteorologinės sąlygos dygimo metu, ypač – kritulių kiekis ir intensyvumas. Sėjos laikas turėjo esminės įtakos rapsų biometriniams rodikliams rudenį prieš žiemojimą. Veislės esminė įtaka nustatyta tik lapų skaičiui pasėjus žieminius rapsus rugpjūčio mėnesį. Pasibaigus atsinaujinusiai vegetacijai rudens–žiemos laikotarpiu, sėjos laiko įtaka rapsų biometriniams rodikliams išliko esminė. Didesnę antžeminės dalies masę, lapų skaičių bei šaknų masę užaugino ‘Kronos’ veislės žieminiai rapsai. Atsinaujinus vegetacijai pavasarį, sėjos laikas turėjo esminės įtakos antžeminės dalies masei bei šaknų masei, tuo tarpu lapų skaičiui esminės įtakos nebuvo. ‘Kronos’ veislės žieminiai rapsai suformavo esmingai didesnę šaknų masę, juos sėjant rugpjūčio 10 d. Trumpas pasiruošimo žiemojimui laikotarpis, nepalankios meteorologinės sąlygos... [toliau žr. visą tekstą] / Data of the field experiment completed on the experiment station at Aleksandras Stulginskis University in the period 2010 – 2011 are analysed in the thesis. Soil of the experiment field - (Calc(ar)i-Epihypogleyic Luvisol). Aim of the research – to estimate the effect of the linear and hybrid winter rape yield formation during the warming autumn – winter period. Sowing time and variety had significant effect on winter rape crop thickness in autumn. Thickness of the crop of the considered winter rape varieties sown August 20, September 5 and 10 differed, considerably. Thicker crop was recorded for the linear rape variety. Meteorological conditions especially precipitation amount and intensity were found to have significant effect on winter rape germination. Sowing time contributed significantly to the biometric rape indices before wintering. The obtained data revealed the effect of variety on the number of winter rape leaves sown in August. The effect of the sowing time after the end of renewed vegetation in autumn-winter period was found to be significant. ‘Kronos’ variety winter rape produced higher above-ground mass, leaves number and root mass. The sowing time was found to have a significant effect not only on the above-ground mass but also on root mass. ‘Kronos’ variety winter rape sown August 10 were recorded to produce considerably higher root mass. Due to unfavourable meteorological conditions at the end of winter the rape sown August 10 and 20 over-wintered. Sowing... [to full text]

Spatial and temporal variations and factors affecting these variations in concentrations of measured parameters at two different groups of stations in Ankara are investigated in this study. The first group consists of three curbside stations that are under the direct influence of traffic emissions, on the other hand, the other group is composed of eight residential stations in which domestic heating is the main emission source. State of air quality in Ankara is determined through comparison with air quality data generated in other countries and available air quality standards. Based on this comparison, although air quality has improved in recent years, it is still not one of the clean cities around the world. Although measured concentrations of pollutants comply with standards in the Turkish Air Quality Regulation, further reduction in concentrations will be necessary, if EU directives become effective in the country. Relation between measured concentrations and meteorological parameters are also investigated. Wind speed and mixing height are the two parameters that are most closely related to measured concentrations at residential stations. However, at curbside stations concentrations are determined by emissions. Qualitative comparison of two groups of stations emphasizes the contribution of motor vehicle emissions on residential areas. Seasonal and diurnal variations of measured parameters and lower winter-to-summer ratio of SO2 indicate contribution of diesel vehicle emissions to SO2 levels at curbside stations. Contribution of traffic emissions are also observed in terms of well defined bimodal traffic pattern of SO2 and PM-10 at non-curbside stations. Seasonal and diurnal pollutant ratios are investigated to apportion different source types that are effective in each group of station. PM-to-SO2, NO-to-NO2, PM-10-to-NOX and SO2-to-NOX ratios are found to be good tracers for qualitative assessment of source groups, namely traffic and domestic heating. Different statistical methodologies are demonstrated to determine the source regions of pollutants with respect to wind direction. Air quality level of Ankara, instead of air quality level in each station, is determined in terms of daily API. One by one correlation between API and meteorological factors are investigated, maximum wind speed and daily thermic excursion is found to be the highest correlated variables. The relation between API and these variables is analyzed by multiple linear regression method and then air pollution forecast model highly correlated with API and meteorological variables is developed. The assimilative capacity of Ankara is calculated in terms of ventilation coefficient and found to be highest in summer and lowest in winter. In winter poor dispersion conditions favor the poor air quality in the city.

Thèse (M.Eng.) -- Université du Québec à Chicoutimi, 2003. / Bibliogr.: f. 182-187. Document électronique également accessible en format PDF. CaQCU