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Introduction: Caffeine has long been used to enhance athletic performance. The research regarding caffeine’s effects on strength and power performance is lacking, especially in female athletes. Purpose: To analyze the acute effects of caffeine on jumping performance and maximal strength in female collegiate athletes. Methods: Eight female collegiate athletes performed two testing sessions separated by one week. Using a double-blind approach, athletes randomly received 6 mg/kg of body mass of caffeine (CAF) or a placebo (PLA). Following 60min of quiet sitting and a standardized warm-up, athletes were tested on measures of squat jump height (SJH) and peak power (SJPP), countermovement jump height (CMJH) and peak power (CMJPP), and isometric mid-thigh pull peak force (IPF) and rate of force development (RFD) on force platforms. Heart rate, systolic blood pressure, diastolic blood pressure, and tympanic temperature were measured at three time points across the testing session. A paired samples t-test with Hedge’s g effect size was used to compare performance results between conditions. A 2 x 3 (condition x time) repeated measures ANOVA was used to analyze changes in physiological measures between and within conditions. Alpha level for all analyses was set at pResults: There were small to moderate differences in SJH (p=0.08, g=0.26), SJPP (p=0.03, g=0.63), CMJH (p=0.004, g=0.27), CMJPP (p=0.18, g=0.20), IPF (p=0.08, g=0.25), and RFD (p=0.22, g=0.40) in favor of caffeine over placebo. Physiological measurements increased similarly across time for both conditions with the exception of SBP, which was greater following caffeine 3 administration compared to placebo (p=0.02). Conclusions: Caffeine ingestion produced small to moderate improvements in jumping performance; however, caffeine failed to significantly affect maximal strength when compared with the placebo. Nonetheless, there was a small increase in IPF and RFD compared to placebo. Therefore, caffeine appears to be an effective ergogenic aid when used to enhance jumping performance and possibly maximal strength in female collegiate athletes.

According to Swedish guidelines for high speed railways on embankment, the total settlement is limited to 20 mm over a track length of 10 m during the construction service life. The main objective of this thesis was to investigate the deformation in the subgrade (unbound layer) in a slab track, since there are very few studies related to high speed railways on high earth structure, discussing particularly the unbound layer. This thesis examined the unbound layer consisting of granular material by using the discrete element method (DEM) software PFC. There was a focus on the material compaction and deformations due to traffic loading. DEM has the benefit to be able to model deformation with due consideration of processes at microscale level. Two different particle shapes were tested: balls and clumps. The results showed that the settlements were small, possibly associated to the well compacted material and the simplifications in the model, such as the shape of the particles, absence of particle breakage and the applied traffic load. The clump simulations resulted in less settlements and permanent strains compared to the ball simulations. The higher the embankment the more settlements but less strains were produced for all the three simulations. One interesting parameter to study for the balls simulation was the friction between the particles. Increased friction contributed to less settlement. The maximum height of the embankment was limited to around 3,2 m due to time restraints. Simulations for higher embankments are needed to be performed in order to better understand the effect of the embankment height on settlements.

In recent years the science revolving image matching algorithms has gotten an upswing mostly due to its benefits in computer vision. This has led to new opportunities for photogrammetric methods to compete with LiDAR data when it comes to 3D-point clouds and generating surface models. In Sweden a project to create a high resolution national height model started in 2009 and today almost the entirety of Sweden has been scanned with LiDAR sensors. The objective for this project is to achieve a height model with high spatial resolution and high accuracy in height. As for today no update of this model is planned in the project so it’s up to each municipality or company who needs a recent height model to update themselves. This thesis aims to investigate the benefits and shortcomings of using photogrammetric measures for generating and updating surface models. Two image matching software are used, ERDAS photogrammetry and Spacemetric Keystone, to generate a 3D point cloud of a rural area in Botkyrka municipality. The point clouds are interpolated into surface models using different interpolation percentiles and different resolutions. The photogrammetric point clouds are evaluated on how well they fit a reference point cloud, the surfaces are evaluated on how they are affected by the different interpolation percentiles and image resolutions. An analysis to see if the accuracy improves when the point cloud is interpolated into a surface. The result shows that photogrammetric point clouds follows the profile of the ground well but contains a lot of noise in the forest covered areas. A lower image resolution improves the accuracy for the forest feature in the surfaces. The results also show that noise-reduction is essential to generate a surface with decent accuracy. Furthermore, the results identify problem areas in dry deciduous forest where the photogrammetric method fails to capture the forest.

Silicon photonics is emerging as a potential field to achieve optical interconnects towards the realization of ultra high bandwidth. The indirect band-gap property of silicon still remains as a big challenge to incorporate silicon photonic active device, for example, silicon-based laser. In the Laboratory of Semiconductor Materials at KTH, a monolithic integration platform based on nano-epitaxial lateral overgrowth (nano-ELOG) technique has been proposed to integrate III-V semiconductor materials with silicon for light source application. The integration process involves uneven surface morphology at different stages. The surfaces of the indium phosphide seed layer on silicon used for ELOG, the mask deposited on it (the silicon/silicon dioxide waveguide) and the ELOG indium phosphide layer grown on it prior to laser growth are often rough. In this thesis work, we have optimized chemical mechanical polishing (CMP) technique in order to achieve an even surface. The same procedure is also necessary to reach the optimal thickness of different layers to enable effective coupling of light from the laser source into the waveguide. CMP of indium phosphide to obtain an average surface roughness of < 1 nm has been optimized by a two-step polishing using different slurries; it results in a step height of ca 3 nm. Similarly the surface of silicon/silicon dioxide “waveguide” has also been optimized with the roughness of ~ 0.5 nm. In the latter case, a step height of 40 nm is retained and this increase with respect to InP is identified to be mainly due to limitations of the polishing machine which is different from that used for indium phosphide. The reduction in step heights with polishing time is analyzed and compared with an existing theoretical model. Our results are in good qualitative agreement with the model. The optimized surface morphology obtained in this work was tested for its suitability for integration. For this evaluation, InP was grown by ELOG in a hydride vapour phase epitaxy reactor with and without CMP of the involved surfaces. The surface after CMP yields layers of better surface morphology with fewer defects as revealed by atomic force microscopy, surface profilometer and cathodoluminescence analysis. The results indicate that the CMP process is useful for monolithic integration for silicon photonics.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This research proposes limit values of height and population density of buildings for a Prospective Management of Seismic Risk in residential areas. The analysis of an efficient evacuation of buildings to the street or refuge area was carried out, evaluating human behavior with models based on the agent, the influence of buildings and the urban parameters of the city with three-dimensional models (BIM) for a severe seismic scenario. The present article establishes that the maximum permissible height of buildings projected in a residential avenue is directly related to the width of the available refuge zone to guarantee the correct evacuation of said zone during a severe seismic event. In addition, an evaluation of a real existing scenario is made in a section of a residential avenue.

Internet of Things (IoT) är ett koncept som fått mycket uppmärksamhet från forskare och utövare av IoT världen över. IoT kan beskrivas som ett nätverk där vardagliga föremål kommunicerar med varandra eller med människor. IoT kommer att bygga ut internet genom att integrera föremål för kommunicering via inbäddade system, detta leder till ett distribuerat nätverk av enheter som kommunicerar med människor och andra IoT-enheter. Härnösand Miljö & Energi AB (HEMAB), är en av ägarna till ServaNet och är ett företag som vill utöka sitt testområde för IoT-sensorer som använder LoRa-teknik för att kommunicera. HEMAB är en av ägarna till ServaNet. Studien har konstruerat metoder för mätning av höjdskillnad från data av en barometer och en accelerometer. Resultatet jämför de två sensorerna med avseende på hur tillförlitligt de kan mäta höjdskillnad över tid. Accelerometern ger mer tillförlitliga resultat som ligger närmare verkligheten, på lägre höjder, med en kortare mätperiod i jämförelse med barometern. Däremot, visar barometern mer tillförlitliga värden på högre höjder, och mer tillförlitligt värde än accelerometern på den högsta testade höjden. Anledningen till att accelerometern ger mindre tillförlitliga resultat på högre höjder med längre mätperiod, beror på det sättet dubbelintegrering tar med sig felande och avstickande värden som blir större och större ju längre tid som integreras. Barometern ger osäkra värden på lägre höjd på grund av att sensorn ger spridda värden redan då den ligger stillastående, detta jämnas ut på högre höjder. LoRaWAN är en lämplig teknik för att kommunicera våghöjd, förutsatt att beräkningar görs på prototypen och endast våghöjden skickas över LoRa, inte sensordata. / Internet of Things (IoT), is a concept that has received a lot of attention from researchers and practitioners of IoT worldwide. IoT can be described as a network where everyday objects communicate with each other or with people. IoT will expand the internet by integrating objects for communication via embedded systems, this leads to a distributed network of devices that communicate with people and other IoT devices. Härnösand Miljö & Energi AB (HEMAB), is one of the owners of ServaNet and is a company that wants to expand its test area for IoT sensors that use LoRa-technology to communicate. HEMAB is one of the owners of ServaNet, as ServaNet is the city network in Härnösand. This study has constructed a method for each sensor that can measure height difference. The result compares a barometer and an accelerometer with respect to how reliably they can measure height difference over time. The accelerometer gives more reliable results that are closer to the reality, at lower altitudes, with a shorter measurement period compared to the barometer. On the other hand, the barometer shows more reliable measurements at higher altitudes, and more accurate measurement than the accelerometer at the highest tested altitude. The reason why the accelerometer performs worse at higher altitudes with longer measurement periods, is due to the way double integration stacks up errors that grows with time, resulting in larger errors for longer periods of measurements. The barometer gives no reliable measurements at lower altitudes, due to the sensor giving scattered values even when the sensor is stationary, this evens out at higher altitudes. LoRaWAN is a suitable technology for communicating wave height, provided that calculations are made on the prototype and only the wave height is sent over LoRa, not sensor-data.  The outcome of the benchmarks measurement showed that increasing the number of nodes would not result in superior performance. It was noted that an optimal number of nodes was found to be between 1 and 20 for all the tests performed. The study showed that no load balancer could be considered a clear winner, instead, different configurations of load balancers performed varyingly well at different tests.

Global Navigation Satellite Systems (GNSS) i kombination med Nätverks-RTK (NRTK) har idag blivit en vanlig metod för geodetiska inmätningar i plan och höjd. Inmätningar med NRTK har fördelen att de är relativt enkel att använda, ger koordinater i realtid och med låg mätosäkerhet (2–3 cm). Dock har användare rapporterat om att större avvikelser i höjd är vanligare än avvikelser i plan, vilka varierar över tid. Tidigare studier har inte funnit samband mellan avvikelser i höjd med NRTK och variationen över tid.  Studiens syfte var att undersöka hur resultatet av inmätta höjder med NRTK varierar över tid och vad som påverkar avvikelsen i höjd samt om det går att finna ett samband för avvikelserna.   I studien användes en GNSS-mottagare med NRTK för att på två stompunkter insamla mätdata en gång i minuten i tre timmar på varje punkt, under totalt två dagar. Mätdata som lagrades och analyserades var antal satelliter, PDOP, vertikal precision, och tidpunkt för inmätt höjd och höjdvärde. Under fältarbetet användes också två olika elevationsvinklar, 10 och 15 grader, för att se hur mätosäkerheten påverkades. Vidare utfördes en dubbelavvägning mellan stompunkterna som en kontroll av de angivna höjdkoordinaterna. Resultatet visar att variationen för enskild inmätt höjd är slumpmässig. En undersökning av PDOP, antal satelliter, horisontell och vertikal precision gav inga korrelationer till mätresultatet. Standardosäkerheten i höjd för mätserie på punkt 8316 med 10° elevationsvinkel beräknades till 1,2 cm och med en förändring till 15° elevationsvinkel 1,6 cm. På punkt 8318 med 10° elevationsvinkel beräknades 2,6 cm och med 15° elevationsvinkel 3,4 cm.  Analysen av mätdata förtydligar att behov finns för att öka tillförlitligheten vid GNSS-mätning med NRTK. Standardosäkerheten överskrider angiven mätosäkerhet för metoden, vid mätning på 8318 med 15° elevationsvinkel. Med elevationsvinkel 10° uppnås inte 68 % av mätningarna inom sigmanivå 2, och drygt 13 % återfinns inom sigmanivå 2–3. Vid en beräkning av standardosäkerhet, med medeltals-bildning, erhölls markanta förbättringar på punkt 8316 för båda mätserierna upp till 20 min medan det följande ger avtagande förbättringar. På punkt 8318 erhölls ständiga förbättringar kontinuerligt till 60 min vilket var den högsta gränsen som undersöktes. Differens mellan högsta och lägsta avvikelse för inmätt höjd, jämfört med känd höjd, beräknades till 9,2 cm för punkt 8316 med 15° elevation och 6,9 cm med 10°. Motsvarande för punkt 8318 med 15° beräknades avvikelsen till 16,5 cm och 12,3 cm för 10°. För GNSS-användare behövs insikt i att enskilda mätningar, med lågt angivna värden i handenheten, inte säkerställer goda mätresultat. Flera mätningar under kort tid kan ge mycket låg standardosäkerhet, men en timme senare kan samma låga standard-osäkerhet för nya mätningar fortfarande representera en avvikande inmätt höjd. Medeltalsbildning, tidsseparation och en lämplig elevationsvinkel är sannolikt krav för att tillförlitligt kunna säkerställa att metoden uppnår 2–3 cm mätosäkerhet i höjd för 68 % av mätningarna. / The usage of GNSS is becoming increasingly more common due to its efficiency and time saving capacities. Network-RTK is a method that uses relative positioning and is supposed to deliver measurements with a positional accuracy of about 2-3 cm for plane and height. Previous research shows variety in measuring results using NRTK at different times or days, but the focus was on other aspects than time itself. This study focused on time and its impact on GNSS-derived heights, linked to used methods for practical use of GNSS, and these results were meant to create guidelines or routines for increased reliability in measuring data if it exceeded the positional accuracy. Measurment data were gathered at two vertical control points during three hours each, on two separate days, with data being collected at a one-minute interval. The findings of this study show that the variety over time is random, and that there are no standard settings or routines that guarantee reliability for the method to deliver commonly stated positional accuracies. Although, we found that certain steps for improving measurements are time-separating, averaged measurements for at least twenty minutes, and a good understanding of how to set an appropriate elevation mask.

The purpose of this investigation was to quantify the magnitude of change in maximal strength and jumping abilities over approximately 1, 2, and 3 years of supervised sport and resistance training in National Collegiate Athletic Association (NCAA) division I women's volleyball athletes. This was an exploratory study on a cohort of women's volleyball athletes (n = 29) split into 3 groups based on the length of the time spent in a supervised resistance training program: Group 1 (n = 11): 0.7 ± 0.3 years, group 2 (n = 9): 1.6 ± 0.2 years, and group 3 (n = 9): 2.4 ± 0.6 years. Monitoring tests consisted of standing height (cm), body mass (kg), body fat (%), static jump height (SJH) and countermovement JH (CMJH) with 0-, 11-, and 20-kg loads (cm), and midthigh clean pull isometric peak force (IPF) and allometrically scaled IPF (IPFa) (Nkg 20.67). Increasing trends were observed for all variables from groups 1 to 2 to 3. Statistically greater improvements (p ≤ 0.05) with moderate to large effect sizes were found between groups 1 and 3 for SJH 0 (19.7%, d = 1.35), SJH 11 (23.8%, d = 1.23), SJH 20 (30.6%, d = 1.20), CMJH 11 (22.6%, d = 1.18), IPF (44.4%, d = 1.22), and IPFa (41.2%, d = 1.32). A combination of traditional resistance training exercises and weightlifting variations at various loads, in addition to volleyball practice, seem to be effective at increasing maximal strength by 44% and vertical JH by 20-30% in NCAA division I women's volleyball athletes after about 2.5 years of training. Furthermore, these characteristics can be improved in the absence of additional plyometric training outside normal volleyball-specific practice.

Through the Cenozoic, paleoclimate records show general trends of global cooling and increased aridity, and environments in North America shifted from predominantly forests to more open habitats. Paleobotanical records indicate grasses were present on the continent in the Eocene; however, paleosol and phytolith studies indicate that open habitats did not arise until the late Eocene or even later in the Oligocene. Studies of large mammalian herbivores have documented changes in ecomorphology and community structure through time, revealing that shifts in mammalian morphology occurred millions of years after the environmental changes thought to have triggered them. Smaller mammals, like rodents and lagomorphs, should more closely track climate and habitat changes due to their shorter generation times and smaller ranges, but these animals have received much less study. To examine changes in smaller mammals through time, we have assembled and analyzed an ecomorphological database of all North American rodent and lagomorph species. Analyses of these data found that rodent and lagomorph community structure changed dramatically through the Cenozoic, and shifts in diversity and ecology correspond closely with the timing of habitat changes. Cenozoic rodent and lagomorph species diversity is strongly biased by sampling of localities, but sampling-corrected diversity reveals diversity dynamics that, after an initial density-dependent diversification in the Eocene, track habitat changes and the appearance of new ecological adaptations. As habitats became more open and arid through time, rodent and lagomorph crown heights increased while burrowing, jumping, and cursorial adaptations became more prevalent. Through time, open-habitat specialists were added during periods of diversification, while closed-habitat taxa were disproportionately lost in subsequent diversity declines. While shifts among rodents and lagomorphs parallel changes in ungulate communities, they started millions of years earlier than in larger mammals. This is likely a consequence of the smaller mammal' greater sensitivity to environmental changes and more rapid evolution. These results highlight the importance of examining understudied members of vertebrate faunas for understanding the evolution of terrestrial communities through time.