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After decades of investigation, we still have to deal withthe problem of environmental effects of the use of de-icingsalt on roads. Lacking useful indicators of the system, westill do not know the environmental utility of ameliorativemeasures taken. The thesis aims at i) describing the system of de-icing practices and theirenvironmental effects with special reference to the exposure ofthe roadside environment to air-borne salt and damage to Norwayspruce seedlings and ii) at proposing indicators for afollow-up system. By collecting bulk deposition and relatingthe deposition pattern to factors concerning wind androad-maintenance characteristics, the influence of thesefactors on air-borne exposure is investigated. By exposingNorway spruce (Picea abies(L.) Karst.) seedlings to roadsideconditions the influence ofsalt exposure on the degree ofdamage is investigated. Based on a comparison of severalsystems of monitoring, improvements are suggested by proposingnew indicators for salt use and its environmental effects. A large part of the salt that is applied on the road surfacewill be transported by air and deposited on the ground in theroadside. While the vast majority of the salt will be depositedwithin some tens of metres of the road, some may still be windtransported several hundred metres away. The wind directionplays an important role for the deposition already at adistance of some ten metres from the road. Wind speedinfluences the distance to which the salt is transported.Chloride concentration in unwashed needles collected after thesalting season is positively related to the bulk deposition ofCl during the exposure. The degree of damage can be describedby a sigmoid curve of response to the Cl concentration inneedles. Improvements to the follow-up system are suggested byproposing indicators of the driving forces, pressures, states,impacts and possible responses as regards the undesired impactson water resources, vegetation and the roadside scenery as asocietal asset. <b>Keywords:</b>road, de-icing salt, air-borne, environmentalimpact, vegetation damage, Norway spruce, seedling, follow-up,monitoring, indicator

<p>After decades of investigation, we still have to deal withthe problem of environmental effects of the use of de-icingsalt on roads. Lacking useful indicators of the system, westill do not know the environmental utility of ameliorativemeasures taken. The thesis aims at</p><p>i) describing the system of de-icing practices and theirenvironmental effects with special reference to the exposure ofthe roadside environment to air-borne salt and damage to Norwayspruce seedlings and ii) at proposing indicators for afollow-up system. By collecting bulk deposition and relatingthe deposition pattern to factors concerning wind androad-maintenance characteristics, the influence of thesefactors on air-borne exposure is investigated. By exposingNorway spruce (<i>Picea abies</i>(L.) Karst.) seedlings to roadsideconditions the influence ofsalt exposure on the degree ofdamage is investigated. Based on a comparison of severalsystems of monitoring, improvements are suggested by proposingnew indicators for salt use and its environmental effects.</p><p>A large part of the salt that is applied on the road surfacewill be transported by air and deposited on the ground in theroadside. While the vast majority of the salt will be depositedwithin some tens of metres of the road, some may still be windtransported several hundred metres away. The wind directionplays an important role for the deposition already at adistance of some ten metres from the road. Wind speedinfluences the distance to which the salt is transported.Chloride concentration in unwashed needles collected after thesalting season is positively related to the bulk deposition ofCl during the exposure. The degree of damage can be describedby a sigmoid curve of response to the Cl concentration inneedles. Improvements to the follow-up system are suggested byproposing indicators of the driving forces, pressures, states,impacts and possible responses as regards the undesired impactson water resources, vegetation and the roadside scenery as asocietal asset.</p><p><b>Keywords:</b>road, de-icing salt, air-borne, environmentalimpact, vegetation damage, Norway spruce, seedling, follow-up,monitoring, indicator</p>

京都大学 / 新制・課程博士 / 博士(農学) / 甲第23949号 / 農博第2498号 / 新制||農||1091(附属図書館) / 学位論文||R4||N5384(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 北島 薫, 教授 神﨑 護, 教授 北山 兼弘 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

Digital Elevation Models (DEM) are a simple representation of the Earth’s surface. DEMs play an important role in the field of remote sensing and GIS and are used as basis for mapping and analysis for a vest majority of scientific applications. There are many ways of producing DEMs, however the direct geo-referencing technology has made Airborne Laser Scanning (ALS) a preferred technology for the acquisition of accurate surface models over broad areas. ALS uses LiDAR (Light Detection and Ranging) which uses light in a form of pulsed laser to measure distances. Before the introduction of the DEM called Ny Nationell Höjdmodell (NNH), the highest level of height data over Sweden was the GSD-altitude data (Geographical Sweden Data). The NNH was a project by Lantmäteriet, where between 2009-2019 the entire Sweden was laser scanned. The product was a new height model called Laser Data NH with positional accuracy of 0,1 m in height and relative accuracy of 0,15 m. This project focuses on testing few methods for consistency assessment between the overlapping strips using linear features. Linear features are extracted for each overlapping area, based on intersection between planar patches extracted from gable rooftops. The first method of this study computes the distance between the overlapping areas without linear features, using two approaches: cloud-to-cloud distance and mesh-to-cloud distance. The second method computes the transformation shifts and rotations needed for the linear features to align by registering the strips with both levelled and not levelled registration. In the third method, distances and angles are measured between the lines, to further analyze how well the strips fit together. The distances are measured as distance between a mid-point of one line in the first LiDAR strip and the line on the second LiDAR strip, for all linear features. The distances were measures both as 3D distances and separately as horizontal and vertical distances. As a final step a hypothesis testing was performed to determine whether the distances and angles between the lines are significant or whether any systematic error is present in the point cloud. Based on the results obtained from the first method, significant distance between the point clouds was obtained. The results from the mesh-to-cloud distance yielded better result with higher uncertainty. According to the second method significant distances between the linear features were obtained based on the registration. The mean absolute error of the registrations showed an error at a dm level, with a minimal rotation in the vertical plane for the coalignment for the levelled registration. The third method showed a mean distance between the linear features of 20 cm. Moreover, this method showed a significant inconsistence between the linear features in the vertical plane based on the high standard uncertainty. / Digitala höjdmodeller (DEM) är en enkel representation av jordens yta. DEM spelar en viktig roll inom fjärranalys och GIS och används som grund för kartläggning och analys för en majoritet av vetenskapliga tillämpningar. Det finns många sätt att producera DEM, men den direkta georefereringstekniken har gjort Airborne Laser Scanning (ALS) till en föredragen teknik för förvärv av exakta ytmodeller över breda områden. ALS använder LiDAR (Light Detection and Ranging) som använder ljus i form av pulserande laser för att mäta avstånd. Före introduktionen av Ny Nationell Höjdmodell (NNH) var den högsta nivån av höjddata över Sverige GSD-höjddata (Geographical Sweden Data). NNH var ett projekt av Lantmäteriet, där mellan 2009-2019 laserscannades hela Sverige. Produkten var en ny höjdmodell som heter Laserdata NH med positionsnoggrannhet på 0,1 m i höjd och relativ noggrannhet på 0,15 m. Detta projekt fokuserar på att testa få metoder för konsekvensbedömning mellan de överlappande remsorna med hjälp av linjära funktioner. Linjära funktioner extraheras för varje överlappande område, baserat på skärningspunkten mellan plana fläckar extraherade från gaveltak. Den första metoden för denna studie beräknar avståndet mellan de överlappande områdena utan linjära funktioner, med två metoder: moln-till-moln-avstånd och nät-till-moln-avstånd. Den andra metoden beräknar de transformationsförskjutningar och rotationer som behövs för att de linjära särdragen ska kola genom att registrera remsorna med både nivellerad och inte nivellerad registrering. I den tredje metoden mäts avstånd och vinklar mellan linjerna, för att ytterligare analysera hur bra remsorna passar ihop. Avstånden mäts som avstånd mellan en mittpunkt på en linje i den första LiDAR-remsan och linjen på den andra LiDAR-remsan, för alla linjära funktioner. Avstånden var mått både som 3D -avstånd och separat som horisontella och vertikala avstånd. Som ett sista steg utfördes en hypotesprovning för att avgöra om avstånden och vinklarna mellan linjerna är signifikanta eller om det finns något systematiskt fel i punktmolnet. Baserat på resultaten från den första metoden erhölls ett betydande avstånd mellan punktmolnen. Resultaten från mask-till-moln-avståndet gav bättre resultat med högre osäkerhet. Enligt den andra metoden erhölls betydande avstånd mellan de linjära särdragen baserat på registreringen. Det genomsnittliga absoluta felet för registreringarna visade ett fel på en dm -nivå, med en minimal rotation i det vertikala planet för samlinjering för den jämnade registreringen. Den tredje metoden visade ett medelavstånd mellan de linjära särdragen på 20 cm. Dessutom visade denna metod en signifikant inkonsekvens mellan de linjära särdragen i det vertikala planet baserat på hög standardosäkerhet.

Air-borne ultrasonic transducers are optimised to achieve a maximal sound pressure in a frequency range around 100 kHz. Moreover, the radiation of a high acoustic power is desired, which requires a large transducer area. Within this dissertation the ultrasonic transducers are, therefore, optimised to operate in the resonance mode. Using this operating point the maximal force is fed into the transducer while it is charged with the lowest loss possible. Many applications of air-borne ultrasound need a sufficient bandwidth in addition to a high sound pressure, that s why the swinging mass of the transducer has to be minimised. For these reasons, air-borne capacitive and piezoelectric film transducers take centre stage of these examinations. New network models of the stripe membrane and the pre-stressed stripe plate are derived to optimise these ultrasonic transducers. Besides its mechanical tension and its bending stiffness, the new network model of the pre-stressed and pressure loaded stripe plate takes also the stiffness caused by the shape of the plate into account. The examined transducers achive a maximal piston velocity around 1 m/s. / Ultraschallwandler für Anwendungen in Luft werden zur Bereitstellung eines maximalen Schalldrucks im Frequenzbereich um 100 kHz optimiert. Sie sollen außerdem die Abstrahlung einer großen Schallleistung zulassen, was eine große Wandlerfläche voraussetzt. Deshalb werden in dieser Arbeit die Ultraschallsender für den Resonanzbetrieb optimiert, wo man die maximale Krafteinspeisung bei minimalen Verlusten einstellt. Viele Anwendungen von Ultraschall in Luft benötigen neben einem hohen Schalldruckpegel auch eine ausreichende Bandbreite, wozu die schwingende Masse der Wandler zu minimieren ist. Deshalb stehen kapazitive und piezoelektrische Folienwandler im Resonanzbetrieb im Vordergrund der Untersuchungen. Zur Optimierung dieser Ultraschallsender werden die Netzwerkmodelle der Streifenmembran und der gespannten Streifenplatte abgeleitet. Neben der mechanischen Spannung und der Biegesteifigkeit berücksichtigt das Netzwerkmodell der gespannten und statisch druckbelasteten Streifenplatte die Formversteifung. Die untersuchten Wandler erreichen eine maximale Kolbenschnelle um 1 m/s.

Air-borne ultrasonic transducers are optimised to achieve a maximal sound pressure in a frequency range around 100 kHz. Moreover, the radiation of a high acoustic power is desired, which requires a large transducer area. Within this dissertation the ultrasonic transducers are, therefore, optimised to operate in the resonance mode. Using this operating point the maximal force is fed into the transducer while it is charged with the lowest loss possible. Many applications of air-borne ultrasound need a sufficient bandwidth in addition to a high sound pressure, that s why the swinging mass of the transducer has to be minimised. For these reasons, air-borne capacitive and piezoelectric film transducers take centre stage of these examinations. New network models of the stripe membrane and the pre-stressed stripe plate are derived to optimise these ultrasonic transducers. Besides its mechanical tension and its bending stiffness, the new network model of the pre-stressed and pressure loaded stripe plate takes also the stiffness caused by the shape of the plate into account. The examined transducers achive a maximal piston velocity around 1 m/s. / Ultraschallwandler für Anwendungen in Luft werden zur Bereitstellung eines maximalen Schalldrucks im Frequenzbereich um 100 kHz optimiert. Sie sollen außerdem die Abstrahlung einer großen Schallleistung zulassen, was eine große Wandlerfläche voraussetzt. Deshalb werden in dieser Arbeit die Ultraschallsender für den Resonanzbetrieb optimiert, wo man die maximale Krafteinspeisung bei minimalen Verlusten einstellt. Viele Anwendungen von Ultraschall in Luft benötigen neben einem hohen Schalldruckpegel auch eine ausreichende Bandbreite, wozu die schwingende Masse der Wandler zu minimieren ist. Deshalb stehen kapazitive und piezoelektrische Folienwandler im Resonanzbetrieb im Vordergrund der Untersuchungen. Zur Optimierung dieser Ultraschallsender werden die Netzwerkmodelle der Streifenmembran und der gespannten Streifenplatte abgeleitet. Neben der mechanischen Spannung und der Biegesteifigkeit berücksichtigt das Netzwerkmodell der gespannten und statisch druckbelasteten Streifenplatte die Formversteifung. Die untersuchten Wandler erreichen eine maximale Kolbenschnelle um 1 m/s.