No / A novel dispersive system operating at 1064-nm excitation and coupled with transfer electron InGaAs photocathode and electron bombardment CCD technology has been evaluated for the analysis of drugs of abuse and explosives. By employing near-IR excitation at 1064-nm excitation wavelength has resulted in a significant damping of the fluorescence emission compared to 785-nm wavelength excitation. Spectra of street samples of drugs of abuse and plastic explosives, which usually fluoresce with 785-nm excitation, are readily obtained in situ within seconds through plastic packaging and glass containers using highly innovative detector architecture based upon a transfer electron (TE) photocathode and electron bombarded gain (EB) technology that allowed the detection of NIR radiation at 1064nm without fluorescence interference. This dispersive near-IR Raman system has the potential to be an integral part in the armoury of the forensic analyst as a non-destructive tool for the in-situ analysis of drugs of abuse and explosives. Copyright (c) 2015 John Wiley & Sons, Ltd.

Muskelstärkande fysisk aktivitet kan likställas med styrketräning och definieras som fysisk aktivitet med avsikt att förbättra eller bibehålla muskulär styrka, muskelvolym och/eller muskulär uthållighet. Explosiv styrka kan beskrivas som kraftutveckling per tidsenhet och är en produkt av styrka/kraft och hastighet. Tidigare studier har visat att en god explosiv och maximal styrka bland annat kan ge hälsovinster, förbättra idrottslig förmåga, minska risken för idrottsskador och kan förebygga fallrisken hos äldre. Isometric mid-thigh pull-test (IMTP) har under de senaste 10 åren blivit ett vanligt test för att mäta helkroppsstyrka hos idrottare. Testet är lätt att administrera och har en god validitet samt reliabilitet. Studiens syfte var att undersöka sambandet mellan explosiv- och maximal styrka hos styrketränande personer vid ett IMTP-test. Tio deltagare med minst ett års erfarenhet av styrketräning rekryterades. Resultatet visade en måttligt stark korrelation (r = 0,48) mellan explosiv och maximal styrka, men ingen statistisk signifikans (p = 0,158). Deltagarnas Peak Force var i genomsnitt 2644 ± 404 N och Peak force vid 250ms var medel 1808 ± 231 N (i medel hade deltagarna uppnått 69% av Peak Force vid 250ms). Sammanfattningsvis noterades att det möjligen kan finnas en trend i korrelationen mellan explosiv och maximal styrka. Detta indikerar att maximal och explosiv styrka troligen överlappar varandra, det kan däremot inte bekräftas då det inte fanns något statistiskt samband. Vidare rekommenderas att framtida forskning undersöker explosiv styrka och maximal styrka som distinkta styrkeförmågor med fler deltagare och standardiserade testmetoder krävs för att vidare undersöka sambandet mellan maximal och explosiv styrka. / Muscle-strengthening physical activity can be equated with strength training and is defined as physical activity with the intention of improving or maintaining muscular strength, muscle volume, and/or muscular endurance. Explosive strength can be described as force development per unit of time and is a product of strength/power and speed. Previous studies have shown that good explosive and maximal strength can yield health benefits, improve athletic performance, reduce the risk of sports related injuries, and prevent the risk of falls in older adults. The Isometric Mid-Thigh-Pull-test (IMTP) has become a common test for measuring whole body strength in athletes over the past 10 years. The test is easy to administer and has good validity and reliability. The aim of the study was to investigate the relationship between explosive and maximal strength in resistance-trained individuals using an IMTP-test. Ten participants with at least one year’s experience of resistance training were recruited. The results showed a moderately strong correlation (r = 0,48) between explosive and maximal strength, but no statistical significance (p = 0,158). The participants’ Peak Force averaged 2644 ± 404 N, Peak Force at 250ms averaged 1808 ± 231 N (on average, participants had received 69% of Peak Force at 250ms). In summary, it was noted that there might be a trend in the correlation between explosive and maximal strength. This suggests that maximal and explosive strength likely overlap, but this cannot be confirmed as there was no statistical significance. Furthermore, it is recommended that future research investigates explosive strength as distinct strength abilities. More participants and standardized testing methods are required to further explore the relationship between maximal and explosive strength

Master of Science / Department of Mechanical and Nuclear Engineering / William L. Dunn / A prototype system for detecting explosives at standoff distances, using a signature based radiation scanning approach, is being developed at Kansas State University. The prototype will incorporate both a machine x-ray source and a machine neutron source to generate signatures from unknown samples of material. These signatures can be compared to templates measured or calculated from known explosive samples using a figure-of-merit. The machine neutron source uses the fusion of deuterium and tritium to create 14.1 MeV neutrons. Due to its radioactivity, the tritium must be sealed within the system. A new method of controlling the gas pressure with the DT generator was developed using a Zr-V-Fe getter supplied by a commercial firm. The shielding and collimation of the 14.1 MeV neutron source is accomplished using layers of steel, high-density polyethylene and borated high-density polyethylene. This thesis describes the development of the gas control method for the sealed neutron source, design studies for the shielding and collimation of the neutron source and modifications made to the building in which the prototype is being housed.

Vid röjning av RSV-ammunition saknas idag adekvat beslutstöd för att dimensionera skadebegränsande åtgärder mot jetstrålens verkan. I uppsatsen vidareutvecklas en beräkningsmodell som författaren tidigare föreslagit. Syftet är att skapa ett verktyg som kan införas i ammunitionsröjningsverksamheten. Fullskaliga skjutförsök har genomförts för att klarlägga inverkan av förhållanden som är typiska vid ammunitionsröjning; en skyddskonstruktion byggd av sandsäckar och med ett långt detonationsavstånd till röjningsobjektet. Försöksresultatet visar att den grundläggande hydrodynamiska penetrationsteorin inte är användbar för dessa förhållanden. Vidare ger sandsäckskonstruktionen signifikant bättre skydd mot jetstrålen än en homogen grusbädd. Genom störningsanalys har känsligheten hos de enskilda parametrarna i beräkningsmodellen för verksamhetstypiska fel utretts. Härefter har Monte Carlo-simulering använts för att analysera den sammanlagda inverkan som dessa fel kan ge. Resultatet har legat till grund för att bestämma modellens säkerhetsmarginal. Militär nytta innebär att modellen skall kunna tillämpas fältmässigt, med korta tidsförhållanden och utan tillgång till avancerade beräkningshjälpmedel. Detta har lett fram till att ett enkelt diagram inkluderats i det kompletta dimensioneringsverktyget. Verktyget föreslås införas i regelverk och utbildningssystem för att avhjälpa den brist som råder idag. / During the clearance of shaped charge ammunition, explosive ordnance disposal (EOD) personnel lack adequate means for the design of protective measures against the jet. In this thesis a calculation model, previously suggested by the author, is developed further. The aim is to create a tool that can be applied to EOD operations. Full-scale experiments have been conducted to clarify the effects of conditions that are typical for EOD operations: protective measures built from sandbags with a long standoff distance to the ordnance. The results indicate that the hydrodynamic penetration theory is not suitable for these conditions. Furthermore, a sandbag construction provides significantly better protection against the jet than a homogeneous gravel construction. By disturbance analysis, the sensitivity of the individual parameters in the model is studied for typical errors. Subsequently, Monte Carlo simulation has been used to analyse the effect these errors can cause. The simulation results have then been the used to determine the model´s margin of safety. Military utility implies that it should be possible to use the model under field conditions, with limited time frames and without access to advanced calculating means. This has resulted in a simple diagram included in the comprehensive design tool. It is proposed that the tool is implemented in regulations and curricula in order to remedy today’s lack of decision support.

Mesoscale models are needed to predict the effect of changes to the microstructure of plastic-bonded explosives on their shock initiation and detonation behaviour. This thesis describes the considerable progress that has been made towards a mesoscale model for two HMX-based explosives PBX9501 and EDC37. In common with previous work in the literature, the model is implemented in hydrocodes that have been designed for shock physics and detonation modelling. Two relevant physics effects, heat conduction and Arrhenius chemistry, are added to a one-dimensional Lagrangian hydrocode and correction factors are identified to improve total energy conservation. Material models are constructed for the HMX crystals and polymer binders in the explosives, and are validated by comparison to Hugoniot data, Pop-plot data and detonation wave profiles. One and two-dimensional simulations of PBX9501 and EDC37 microstructures are used to investigate the response of the bulk explosive to shock loading. The sensitivity of calculated temperature distributions to uncertainties in the material properties data is determined, and a thermodynamic explanation is given for time-independent features in temperature profiles. Hotspots are widely accepted as being responsible for shock initiation in plastic-bonded explosives. It is demonstrated that, although shock heating of crystals and binder is responsible for temperature localisation, it is not a feasible hotspot mechanism in PBX9501 and EDC37 because the temperatures generated are too low to cause significant chemical reaction in the required timescales. Critical hotspot criteria derived for HMX and the binders compare favourably to earlier studies. The speed of reaction propagation from hotspots into the surrounding explosive is validated by comparison to flame propagation data, and the temperature of the gaseous reaction products is identified as being responsible for negative pressure dependence. Hotspot size, separation and temperature requirements are identified which can be used to eliminate candidate mechanisms in future.

Blast-induced traumatic brain injury (bTBI) has been described as the defining injury of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF). Previously, most blast injury research has focused on the effects of blast on internal, gas filled organs due to their increased susceptibility. However, due to a change in enemy tactics combined with better armor and front-line medical care, bTBI has become one of the most common injuries due to blast. Though there has been a significant amount of research characterizing the brain injury produced by blast, a sound understanding of the contribution of each component of the shockwave to the injury is needed. Large animal models of bTBI utilize chemical explosives as their shockwave source while small animal models predominantly utilize compressed air-driven membrane rupture as their shockwave source. We designed and built a multi-mode shock tube capable of utilizing compressed gas (air or helium)-driven membrane rupture or chemical explosives (oxyhydrogen – a 2:1 mixture of hydrogen and oxygen gasses, or RDX – high order explosive) to produce a shockwave. Analysis of the shockwaves produced by each mode of the McMillan Blast Device (MBD) revealed that compressed air-driven shockwaves exhibited longer duration positive phases than compressed helium-, oxyhydrogen-, or RDX-driven shockwaves of similar peak overpressure. The longer duration of compressed air-driven shockwaves results in greater energy being imparted on a test subject than would be imparted by shockwaves of identical peak overpressures from the other sources. Animals exposed to compressed air-driven shockwaves exhibited more extensive brain surface hematoma, more blood-brain barrier compromise, more extensive reactive astrocytosis, and greater numbers of activated microglia in their brains than did animals exposed to oxyhydrogen-driven shockwaves of even greater peak overpressure. Taken together, these data suggest that compressed air-driven shockwaves contain more energy than their chemical explosive-derived counterparts of equal peak overpressure and can result in greater injury in an experimental animal model. Additionally, these data suggest that exposure to longer duration shockwaves, which is common in certain realworld scenarios, can result in more severe bTBI. The results of this study can be used to aid design of blast wave mitigation technology and future clinical intervention.

<p>In the boreal forests of the Northern Hemisphere, time series of tree-ring width (TRW) and maximum density in the latewood (MXD) are highly correlated to local instrumental summer-temperature data and are thus widely used as proxies in high-resolution climate reconstructions. Hence, much of our present knowledge about climatic variability in the last millennium is based on tree-rings. However, many tree-ring records have a lack of data in the most recent decades, which severely hampers our ability to place the recent temperature increase in a longer-timescale perspective of natural variability.</p><p>The main objective of this thesis is to update and extend the Torneträsk TRW and MXD records in northern Sweden. Local instrumental climate-data is used to calibrate the new tree-ring records. The results show that TRW is mainly forced by temperature in the early growing season (June/July) while MXD has a wider response window (June – August) and has a higher correlation to temperature. Two reconstructions of summer temperature are made for (i) the last 7,400 years based on TRW, and (ii) the last 1,500 years based on a combination of TRW and MXD. The reconstructions show natural variability on timescales from years to several centuries. The 20th century does not stand out as a notably warm period in the long timescale perspective. A medieval period from AD 900 – 1100 is markedly warmer than the 20th century.</p><p>The environmental impact from a large explosive volcanic eruption in 1628/1627 BC is analysed in the tree rings of 14C-dated bog pines in south-central Sweden and in absolutely-dated subfossil pines from Torneträsk. The results show evidence of an impact in the southern site at approximately this time but no detectable impact in the North. </p><p>Subfossil trees of Fitzroya cupressoides in southern Chile were 14C-dated to approx. 50,000 years BP and amalgamated into a 1,229-year TRW chronology. This tree-ring record is the oldest in the world. The variability in this Last-glacial chronology is similar to the variability in present-day living trees of the same species. These results suggest that the growth–forcing mechanisms 50,000 years ago were similar to those at present.</p>

In the boreal forests of the Northern Hemisphere, time series of tree-ring width (TRW) and maximum density in the latewood (MXD) are highly correlated to local instrumental summer-temperature data and are thus widely used as proxies in high-resolution climate reconstructions. Hence, much of our present knowledge about climatic variability in the last millennium is based on tree-rings. However, many tree-ring records have a lack of data in the most recent decades, which severely hampers our ability to place the recent temperature increase in a longer-timescale perspective of natural variability. The main objective of this thesis is to update and extend the Torneträsk TRW and MXD records in northern Sweden. Local instrumental climate-data is used to calibrate the new tree-ring records. The results show that TRW is mainly forced by temperature in the early growing season (June/July) while MXD has a wider response window (June – August) and has a higher correlation to temperature. Two reconstructions of summer temperature are made for (i) the last 7,400 years based on TRW, and (ii) the last 1,500 years based on a combination of TRW and MXD. The reconstructions show natural variability on timescales from years to several centuries. The 20th century does not stand out as a notably warm period in the long timescale perspective. A medieval period from AD 900 – 1100 is markedly warmer than the 20th century. The environmental impact from a large explosive volcanic eruption in 1628/1627 BC is analysed in the tree rings of 14C-dated bog pines in south-central Sweden and in absolutely-dated subfossil pines from Torneträsk. The results show evidence of an impact in the southern site at approximately this time but no detectable impact in the North. Subfossil trees of Fitzroya cupressoides in southern Chile were 14C-dated to approx. 50,000 years BP and amalgamated into a 1,229-year TRW chronology. This tree-ring record is the oldest in the world. The variability in this Last-glacial chronology is similar to the variability in present-day living trees of the same species. These results suggest that the growth–forcing mechanisms 50,000 years ago were similar to those at present.

Random graph processes are basic mathematical models for large-scale networks evolving over time. Their systematic study was pioneered by Erdös and Rényi around 1960, and one key feature of many 'classical' models is that the edges appear independently. While this makes them amenable to a rigorous analysis, it is desirable, both mathematically and in terms of applications, to understand more complicated situations. In this thesis the main goal is to improve our rigorous understanding of evolving random graphs with significant dependencies. The first model we consider is known as an Achlioptas process: in each step two random edges are chosen, and using a given rule only one of them is selected and added to the evolving graph. Since 2000 a large class of 'complex' rules has eluded a rigorous analysis, and it was widely believed that these could give rise to a striking and unusual phenomenon. Making this explicit, Achlioptas, D'Souza and Spencer conjectured in Science that one such rule yields a very abrupt (discontinuous) percolation phase transition. We disprove this, showing that the transition is in fact continuous for all Achlioptas process. In addition, we give the first rigorous analysis of the more 'complex' rules, proving that certain key statistics are tightly concentrated (i) in the subcritical evolution, and (ii) also later on if an associated system of differential equations has a unique solution. The second model we study is the H-free process, where random edges are added subject to the constraint that they do not complete a copy of some fixed graph H. The most important open question for such 'constrained' processes is due to Erdös, Suen and Winkler: in 1995 they asked what the typical final number of edges is. While Osthus and Taraz answered this in 2000 up to logarithmic factors for a large class of graphs H, more precise bounds are only known for a few special graphs. We close this gap for the cases where a cycle of fixed length is forbidden, determining the final number of edges up to constants. Our result not only establishes several conjectures, it is also the first which answers the more than 15-year old question of Erdös et. al. for a class of forbidden graphs H.

L’objectif de cette étude est de concevoir et caractériser une plate-forme micro-fluidique permettant la concentration et la séparation d’un produit de dégradation du trinitrotoluène :l’ortho-nitrotoluène (ONT) considéré comme un traceur de composés explosifs. Les capteurs àbase de dioxyde d’étain (SnO2) utilisés ici comme détecteurs présentent un réel manque desélectivité et leur sensibilité peut s’avérer insuffisante pour la détection de traces de polluantsdans l’atmosphère. L’approche originale envisagée dans cette étude consiste à travailler en amontdu capteur chimique (SnO2), en particulier, en développant d’une part un micro-préconcentrateurde gaz afin d’améliorer l’aspect sensibilité et d’autre part une micro-colonne chromatographiquepour s’affranchir du manque de sélectivité.Dans un premier temps, une série d’adsorbants ont été étudiés et caractérisés pour laconcentration de l’ONT. Les résultats obtenus ont permis de sélectionner trois types de charbonsactifs (N, KL2 et KL3) et une zéolithe hydrophobe DAY.Ensuite, les micro-systèmes fluidiques ont été réalisés sur un substrat de silicium et élaborés enutilisant la technologie silicium/verre.La dernière partie de ce travail est consacrée à l’évaluation des performances d’analyse de cetteplate-forme en termes de concentration et de séparation de l’ONT. En particulier, après avoirévalué les conditions optimales de concentration et d’élution de l’ortho-nitrotoluène, le couplageentre la plate-forme micro-fluidique et le capteur à base de dioxyde d’étain a permis d’une part demontrer que la limite de détection de l’ortho-nitrotoluène est inférieure à 365 ppb. Dans ce cas,une désorption totale de la molécule cible et un facteur de concentration constant ont été obtenusavec la zéolithe DAY. D’autre part, l’utilisation de ce type de plate-forme a permis d’obtenir unebonne performance de détection et de séparation de l’ONT en présence d’un interférent (toluène)et d’un taux d’hygrométrie élevé. / The objective of this study is to develop and characterize a micro-fluidic platform allowing theconcentration and the separation of a degradation compound of trinitrotoluene: the orthonitrotoluenerecognized as an explosive taggants. Tin dioxide gas sensors (SnO2) used here asdetectors suffer from a luck of selectivity and have an insufficient sensitivity toward most ofpollutants. For that, our original approach consists to work in front of a chemical gas sensor(SnO2), in particular, by developing on the one hand a gas micro-preconcentrator to improve thesensitivity and on the other hand, a chromatographic micro-column in order to overcome the luckof selectivity.First, various adsorbents have been studied and characterized for the ONT concentration. Theobtained results allowed to select three types of activated carbons (N, KL2 and KL3) and ahydrophobic zeolite DAY. Then, the micro-system devices have been realized on a siliconsubstrate and manufactured using the silicon/glass technology.The last part of this work is devoted to the evaluation of the platform performances in terms ofconcentration and separation of ONT. In particular, after the optimization of the experimentalconditions concerning the concentration and the elution of ortho-nitrotoluene, the couplingbetween the micro-fluidic platform and a tin dioxide gas sensor allowed on the one hand to showthat the detection limit of the ONT pollutant is lower than 365 ppb. In this case, a total desorptionof the analyte and a constant concentration factor were obtained with the zeolite DAY. On theother hand, the use of this type of platform allowed to obtain a good separation and detectionperformance of ONT in presence of interferent (toluene) and at high humidity rate