Dissertations / Theses on the topic 'Bulk'

SMS-trafiken världen över ökar hela tiden och användningsområdena blir fler. Flera företag har börjat använda SMS som ett medium att kontakta sina kunder, de allra vanligaste brancherna som utnyttjar detta är banker, logistikföretag och läkarmottagningar. När ett företag vill SMSa ut till sina kunder så går SMSet via en aggregatör som har kontakter med flera operatörer. En aggregatörs framgång är beroende av att så många SMS som möjligt kommer fram, för det är på det de tjänar pengar. Denna rapport utreder därför på vilket sätt man kan mäta kvalité på SMS-utskick hos en aggregatör och med kvalité avses leveranssäkerhet, leveranstid och genomströmningshastighet. Arbetets första delar handlar om vad en aggregatör gör och vad kvalité är för en aggregatör, samt de tekniska bitarna som finns kring SMS såsom GSM och SMPP. Den data som har analyserats kommer ifrån en databas hos en aggregatör och tillsammans med vetskapen ifrån bakgrundsarbetet så har resultatet blivit åtta stycken olika mätningar som tillsammans mäter de kvalitéaspekter en aggregatör har. Med de mätmetoder som presenteras i detta arbete är det fullt möjligt att med ett monitoreringsverktyg få överblick av SMS-trafiken hos en aggregatör.

 

Piezoelectric voltage transformers (PTs) can be used to transform an input voltage into a different, required output voltage needed in electronic and electro- mechanical systems, among other varied uses. On the macro scale, they have been commercialized in electronics powering consumer laptop liquid crystal displays, and compete with an older, more prevalent technology, inductive electromagnetic volt- age transformers (EMTs). The present work investigates PTs on smaller size scales that are currently in the academic research sphere, with an eye towards applications including micro-robotics and other small-scale electronic and electromechanical sys- tems. PTs and EMTs are compared on the basis of power and energy density, with PTs trending towards higher values of power and energy density, comparatively, indicating their suitability for small-scale systems. Among PT topologies, bulk disc-type PTs, operating in their fundamental radial extension mode, and free-free beam PTs, operating in their fundamental length extensional mode, are good can- didates for microfabrication and are considered here. Analytical modeling based on the Extended Hamilton Method is used to predict device performance and integrate mechanical tethering as a boundary condition. This model differs from previous PT models in that the electric enthalpy is used to derive constituent equations of motion with Hamilton’s Method, and therefore this approach is also more generally applica- ble to other piezoelectric systems outside of the present work. Prototype devices are microfabricated using a two mask process consisting of traditional photolithography combined with micropowder blasting, and are tested with various output electri- cal loads. 4mm diameter tethered disc PTs on the order of .002cm

3 , two orders smaller than the bulk PT literature, had the followingperformance: a prototype with electrode area ratio (input area / output area) = 1 had peak gain of 2.3 (± 0.1), efficiency of 33 (± 0.1)% and output power density of 51.3 (± 4.0)W cm

-3 (for output power of80 (± 6)mW) at 1M? load, for an input voltage range of 3V-6V (± one standard deviation). The gain results are similar to those of several much larger bulk devices in the literature, but the efficiencies of the present devices are lower. Rectangular topology, free-free beam devices were also microfabricated across 3 or- ders of scale by volume, with the smallest device on the order of .00002cm

3 . These devices exhibited higher quality factorsand efficiencies, in some cases, compared to circular devices, but lower peak gain (by roughly 1/2 ). Limitations of the microfab- rication process are determined, and future work is proposed. Overall, the devices fabricated in the present work show promise for integration into small-scale engi- neered systems, but improvements can be made in efficiency, and potentially voltage gain, depending on the application

Objetivo: Comparar in vitro la resistencia a la compresión y resistencia flexural de resinas Bulk Fill (Opus™ Bulk Fill, Tetric® N-Ceram Bulk Fill y Filtek™ Bulk Fill) Materiales y métodos: Se confeccionaron 132 especímenes en total: G1/G5: Opus™ Bulk Fill, G2/G6: Tetric® N-Ceram Bulk Fill, G3/G7: FiltekTM Bulk Fill y G4/G8: FiltekTM Z350XT (grupo control). Cincuenta y seis especímenes cilíndricos (3x5mm) para evaluar la resistencia a la compresión, divididos en 4 grupos (n=14): G1, G2, G3 y G4 y setenta y seis especímenes rectangulares para evaluar la resistencia flexural, divididos en 4 grupos (n=19): G5, G6, G7 y G8. Las pruebas mecánicas se realizaron en una máquina de ensayo universal Instron® con una carga de 100kN a 1mm/1min (Resistencia Compresiva) y una velocidad de 1mm/1min (Resistencia Flexural). El análisis de datos se realizó mediante estadística descriptiva e inferencial (test de Kruskal Wallis /prueba post hoc). Resultados: Para la resistencia a la compresión, los resultados fueron: G1 (141.68 MPa ± 22.20), G2 (139.03 MPa ± 23.56), G3 (235.59 MPa ± 26.08) y G4 (99.28 MPa±11.36). Se encontró diferencias estadísticamente significativas entre todas las resinas evaluadas (p<0.001). Para resistencia flexural los resultados fueron: G5 (116.29 MPa ± 7.20), G6 (109.67 MPa ± 7.58), G7 (200.53 MPa ± 10.32) y G8 (90.08 MPa ± 8.63). Se encontró diferencias estadísticamente significativas entre todas las resinas evaluada (p<0.001). Conclusiones: La resina Filtek™ Bulk Fill presentó mayor resistencia a la compresión y flexural en relación a las resinas evaluadas.
Objective: Compare in vitro the compressive strength and flexural strength of Bulk fill resin composite (Opus™ Bulk Fill, Tetric® N-Ceram Bulk Fill y Filtek™ Bulk Fill). Method and materials: 132 specimens were made: G1/G5: Opus™ Bulk Fill, G2/G6: Tetric® N-Ceram Bulk Fill, G3/G7: FiltekTM Bulk Fill y G4/G8: FiltekTM Z350XT (control group). Fifty-six cylindrical samples (3x5mm) to evaluate the compressive strength, divided in 4 groups (n=14): G1, G2, G3 y G4 and seventy-six rectangular samples to evaluate flexural strength, divided in 4 groups (n=19): G5, G6, G7 y G8. The mechanical tests were made with the Instron® Universal Testing Machine at crosshead speed of 1.0 mm/min with a load of 100 kN to compressive strength and at crosshead speed of 1.0 mm/min to flexural strength. The data analysis was performed by descriptive and inferential statistics (test de Kruskal Wallis /test post hoc). Results: For the compressive strength, the results were: G1 (141.68 MPa± 22.20), G2 (139.03 MPa ± 23.56), G3 (235.59 MPa ± 26.08) y G4 (99.28MPa±11.36). Statistically significant differences were found between all the groups (p> 0.001). For flexural strength the results were: G5 (116.29MPa ± 7.20), G6 (109.67 MPa ± 7.58), G7 (200.53 MPa ± 10.32) y G8 (90.08 MPa ±8.63). Statistically significant differences were found between all the groups (p> 0.001). Conclusion: Filtek ™ Bulk Fill resin composite showed greater compressive and flexural strength in comparison to the other resins evaluated.
Tesis

In this study molecular dynamics simulation program in NVT ensemble using Velocity Verlet integration was written in order to investigate the glass forming ability of two metallic systems. The Zn-Mg system, one of the frontiers of simple metal-metal metallic glasses and Fe-B, inquiring attention due to presence of many bulk glass forming alloy systems evolved from this binary with different alloying element additions. In addition to this, atomistic calculations on the basis of ordering were carried out for both Zn-Mg and Fe-B systems. Ordering energy values are calculated using electronic theory of alloys in pseudopotential approximation and elements which increase the ordering energy between atoms were determined. The elements which increase the ordering energy most were selected as candidate elements in order to design bulk amorphous alloy systems. In the experimental branch of the study centrifugal casting experiments were done in order to see the validity of atomistic calculations. Industrial low grade ferroboron was used as the master alloy and pure element additions were performed in order to constitute selected compositions. Fe62B21Mo5W2Zr6 alloy was successfully vitrified in bulk form using nearly conventional centrifugal casting processing. Specimens produced were characterized using SEM, XRD, and DSC in order to detect the amorphous structure and also the crystalline counterpart of the structure when the cooling rate is lower. Sequential peritectic and eutectic reaction pattern was found to be important for metallic glasses which can be vitrified in bulk forms with nearly conventional solidification methods.

The turning and drilling of Zr52.5Ti5Cu17.9Ni14.6Al10 metallic glass (BMG) are evaluated in this study. The mechanics of machining and chip formation and characterization are investigated. In the lathe turning of BMG, above a threshold cutting speed, the low thermal conductivity of BMG leads to chip temperatures high enough to cause the chip oxidation and associated light emission. The high temperature produced by this exothermic chemical reaction causes crystallization within the chips. Oxide layer, amorphous region, fully crystalline region, and crystalline-amorphous transition region are observed in the cross-section of the chips. The x-ray diffraction peaks match the pattern for monoclinic ZrO2. Turning chips morphology suggests that increasing amounts of viscous flow control the chip-removal process. Moreover, viscous flow and crystallization can occur during the machining of the bulk metallic glass, even under the high temperature gradient and strain rate. For the BMG chip without light emission, the serrated chip with adiabatic shear band and void formation was observed. High cutting speed significantly reduced the forces for BMG machining due to thermal softening. Roughness of machined BMG surfaces is generally better than that of Al6061-T6 and SS304. Tool wear is a problem for BMG turning. Chipping and thermal softening on the lathe tool cutting edges can be observed. Drilling of BMG shows that holes with precision geometry and good surface roughness can be efficiently produced in BMG using the high speed steel and WC-Co drills at spindle speed that does not exceed the limit for chip light emission. Morphology of BMG drilling chip are classified and analyzed. The thermal conductivity of tool material and cutting speed are concluded as two critical factors that triggered the chip exothermic oxidation and light emission. The chip light emission has profound impact on the drill wear, as shown by the experimentally measured thrust force and torque. This study concludes the precision machining of BMG is possible with the selection of feasible tools and process parameters.

This thesis deals with an area of queueing theory which, despite its obvious applicability to real-life, has received relatively little attention in the literature, the field of bulk-arrival, bulk-service, multi-channel queueing systems. In particular attention is focused on approximating the expected number in the queueing system in a steady state. The aim of this thesis is to provide the practitioner with a straightforward and reasonably accurate mans of calculating the expected number in the system. An introduction will be given to the subject area and the relevant literature will be reviewed. An approximation will be formulated to the mean number of a multi-channel simple queueing system based on the mean number in a single-channel simple queueing system. Multi-channel, bulk arrival systems are then considered. For systems with a fixed arrival batch size two methods are derived to approximate the mean number in the system, one simple straight line based method and one, more complicated, quadratic based approach. Probabilistic arrival batch size distributions are then considered, and a recursive approximation developed to the mean number in the system. The concept of bulk-service is introduced and formulae derived for the mean number in the system for fixed arrival batch sizes and probabilistic arrival batch sizes. Finally attention is given to how the methods derived could be extended to include all possible multi-channel, bulk-arrival and bulk-service queueing systems. Some suggestions for the future are given.

Introduction Low melting point metals are often encapsulated in a hermetic container, irradiated and the container transferred to hot-cell for material removal and processing. An important process of this kind is the production of 82Sr from rubidium (melting point: 39.5 °C.) This new concept departures completely form the encapsulated targets approach and allows an almost continues production by the irradiation of the bulk metal. As well, eliminated is the target transfer. By placing the target material dissolution chamber right in the target station, only the dissolution product is pumped to the hotcell for further processing. Material and Methods Some of the disadvantages of the encapsulated target are: 1. Complicated transfer system that is ex-pensive to install, slow and prone to failures. 2. Complex and expensive encapsulation procedure. 3. Loss of production time during the lengthy target changing. 4. Capsule geometry is constrained by the encapsulating process and transfer demands compromising heat transfer and beam power. To avoid the difficulties of liquid metal handling, metal salts are often used instead (rubidium chloride is one example). This creates other problems and limits the beam currents and production yields. In the system described, the liquid metal is transferred (by gravity) from a bulk container to an irradiation chamber. The chamber, made out of nickel-plated silver, holds the correct quantity of rubidium for one irradiation run. Because of the geometry of the chamber and the efficient cooling, up to 40KW of beam power can be delivered to the target. The chamber is equipped with thermocouples and a liquid-metal level detector and is entirely of welded/brazed construction. The alloy foil that forms the beam window is electron-beam welded to the chamber front ring. At the end of irradiation the irradiated liquid metal is gravity fed into a reaction chamber situ-ated below the irradiation chamber, and a new load of fresh rubidium released into the irradia-tion chamber. The liquid-metal transfer and the irradiation components are shown on FIG. 1, and the sectional view on FIG. 2. Appropriate chemicals (n-butanol in the case of rubidium) are delivered to the reaction chamber and the irradiated metal dissolved. The liquid dissolution product is transferred back to the hotcell. Since all steps of the reaction involve liquids, only small diameter tubes connect the target station with the hotcell. The transfer is fast and simple. The bulk liquid-metal storage container can be constructed to hold enough material for 10 or more runs. When empty, it is replaced with a pre-loaded one. The container is connected to the target system with one coupling and the exchange takes a short time. A robotic bottle exchange can be implemented if desired. The station is equipped with its own vacuum system, beam diagnostic (consisting of a four-sector mask) and a collimation. The target chamber and each of the beam intercepting components are electrically insulated to allow beam current monitoring. Constructed entirely out of metal and ceramic the target core assembly does not suffer from radiation damage. The use of aluminum, silver and alumina reduce component activation. Results and Conclusion A large part of the station design is based on the well proven construction of high current solid target system and is using the same, or similar components. Test was performed to optimize the liquid-metal transfer and the chamber filling with the correct volume, while leaving some room for expansion. A process for niobium coating of sliver is investi-gated. Niobium is known to provide good corro-sion resistance against liquid metals. Thermal modelling of the target and flow analysis of the cooling geometry is under way.

Master of Science
Department of Grain Science and Industry
Kingsly Ambrose
Consistent and reliable flow of bulk wheat from hoppers and silos is very significant in wheat handling and processing. Bulk wheat flow challenges such as inconsistent flow, arching, etc., are common during handling. The irregular size and non-uniformity of physical properties, the presence of impurities affects the flow behavior during discharge. Chaff and insects infested kernels are the two most common impurities present in wheat. In this research, the effect of these two impurities on their physical and flow properties of wheat were studied. Physical and flow indicators, such as bulk, tapped, particle densities, angle of repose, Hausner’s ratio, Carr index, and porosity measures the flowability of uncompacted bulk solids. Meanwhile, flow properties tested by shear testing principle based on Jenike’s method, simulated bulk wheat under pressure in bins/hoppers. The dynamic properties tested quantify the energy required to flow, compressibility and permeability at dynamic handling situations. Due to the presence of impurities and moisture content differences, bulk density and angle of repose of wheat varied from 801.54kg/m3 to 718.36kg/m3, and 23.6° to 38.4°, respectively. Angle of internal friction and wall friction angle that reflect interaction between particles and particle with bins/hopper walls, ranged from 23.95° to 43.13° and 15.46° to 20.33°, respectively. In addition to instrumental flow property evaluation, the flow profile, discharge rate, and particle velocity during hopper flow of bulk wheat was studied using Particle Image Velocimetry method. Mass flow and funnel flow hopper dimensions were used for this flow profile analysis. The discharge rate decreased from 1.67 to 1.12 kg/s for mass flow and 1.42 to 0.86 kg/s for funnel flow when the chaff in bulk wheat increased from 0% to 7.5% (weight basis). Analysis of the active flow zone indicated that bulk wheat without chaff had a uniform flow compared to wheat with chaff in the bulk. The findings from this study will be useful for design of hopper bottom bins and handling equipment based on the wheat quality and percent moisture content.

Transport properties of bulk unipolar (barrier) devices are investigated in the steady-state mode. This has entailed the study of heavily doped silicon characteristic which comprises important regions of the multilayer bulk unipolar devices. The devices covered are Camel diodes, P-plane barrier diodes and open-base bipolar transistors. Two operating modes are distinguished: the punchthrough mode, and the non punch-through (bipolar) mode. A combination of thermionic and diffusion mechanisms is used in the current - voltage analysis. Minority carrier transport at the polysilicon - monosilicon interface is also studied in polysilicon emitter bulk unipolar diodes with the emphasis having been placed on the influence of heavy doping; the aim being the development of a useful predictive tool for the study of these structures in which transistor action can be obtained due to the mechanism of barrier height modulation via minority-carrier injection. The validity of the analysis is evaluated by comparison with available experimental results. A new form of multigrain - barrier bulk unipolar diode structure has been proposed and analyzed using the carrier trapping model at the grain boundary of the polysilicon. Heavy doping effects / parameters are included in the developed analysis. As it stands, the present model helps in fulfilling the purpose of giving an insight into the physical mechanism of charge carrier transport with heavy doping at a fundamental level and providing a tool for the examination of the behaviour of alternative device configurations. However, heavy doping effects are revealed as being of profound importance in the determination of bulk unipolar device characteristics.

Photoluminescence (PL) has been studied from different types of bulk GaN samples grown by hydride vapor phase epitaxy technique at Kyma Technologies. Point defects in bulk and at the surface affect the electrical and optical properties of GaN and could be analyzed by PL. The surface of the samples was polished with different techniques: one is chemical mechanical polish (CMP) and another is mechanical polish (MP). PL data from MP and CMP surfaces show that PL intensity from the CMP-treated surface is much higher than that from the MP-treated surface. This can be explained by defects formed during the process of MP polish. However, after the MP-treated surface is etched with RIE method, the optical quality of the MP-treated surface improves. In particular, as the depth of etching increases from 50 nm to 700 nm, the PL intensity increases by a factor of 1000. PL from the CMP surfaces of undoped bulk GaN samples contains a broad red luminescence (RL) band and a broad green luminescence (GL) band. However, PL from the CMP surfaces of Fe-doped GaN samples contained a blue luminescence band (labeled as BL2 in literature) and the yellow luminescence (YL) band. PL from MP-treated surfaces (both undoped and Fe-doped) was very weak and it contained relatively narrow red and green bands. These bands, labeled RL2 and GL2, respectively, are quenched at relatively low temperatures, in contrast to the RL and GL bands which are almost independent of temperature in the range from 15 to 300 K.

In this thesis, we study kinetic theory and chiral perturbation theory, which are employed to compute the bulk viscosity of a gas of pions at temperatures below the QCD crossover temperature, for the physical value of m, to lowest order in chiral perturbation theory. Bulk viscosity is controlled by number-changing processes which become exponentially slow at low temperatures when the pions become exponentially dilute, leading to an exponentially large bulk viscosity ζ ∼ (F^8/m^5)*exp(2m/ T), where F ≃ 93 MeV is the pion decay constant.
La théorie cinématique des particules et la théorie perturbative chirale sont d'abord presentées. Grâce à ces outils, la viscosité volumique d'un gaz de pions à une température en-deçà de la température de transition de phase de la chromodynamique quantique est calculée pour la valeur expérimentale de m, au premier ordre de la théorie perturbative. À basse température, les processus affectant le nombre de particules ralentissent de manière exponentielle lorsque la densité des pions devient exponentiellement faible. Ces processus contrôlent la viscosité volumique, qui à son tour devient exponentiellement large ζ ∼ (F^8/m^5)*exp(2m/T), pour une constante de désintegration des pions F ≃ 93 MeV.

The proposed study had been performed behind the premise of proposing a methodology for estimating the current operational risk of bulk carriers. Hence, a high level risk assessment has been conducted for evaluating the safety performance of dry bulk cargo transportation. This included the preparatory step for setting the problem's boundary limits, hazard identification for the prioritization of causes and effects, risk analysis for the quantification of risks and risk evaluation for assessing the significance and the acceptability of the estimated risk. The relevant aspects that are taken into account consist of the vessel's function (carriage of payload), operational phase (ocean transit), external (weather conditions, routeing) and internal (cargoes) influences, accident category (foundering) and the risk associated with crew (fatalities) and property (loss of vessel and cargo). Apparently, many factors were competing for attracting attention, and therefore, the Pareto principle was applied for narrowing the analysis where corrosion was identified as a main situation of causing harm. The attached uncertainty in the aforementioned operational domain is dealt with the Bayesian Networks technology and concurrently the construed prioritization to corrosion is verified by the developed risk model. The estimated risk was found As Low As Reasonably Practicable and the potential of improvement is considered by addressing preventive (design) and mitigating (operational) measures. Furthermore, their effectiveness as action implementing risk management decision is illustrated by employing Life Cycle Cost Analysis, a decision making technique for exploiting different investment opportunities.

This research is concerned with the study of bulk queueing models. A number of M/G/l queues with bulk-arrival and/or bulk-service are studied via the imbedded Markov chain technique to derive steady-state models. Results from these models are compared with simulation results after the appropriate numerical analysis, needed to implement these solutions, has been considered. Similar queueing models are considered from a time-dependent viewpoint. Because of the difficulties of obtaining time-dependent solutions, the emphasis is placed upon the development of approximations to the queueing results. Finally, to demonstrate the practicability of these models, two real-life problems are considered, namely the Gatwick Rapid Transit systems and the proposed Channel Tunnel freight shuttle operation. It is demonstrated that the former is an under-utilised system, while the latter is likely to operate very close to its capacity conditions.

Approved for public release, distribution unlimited
Approved for public release, distribution unlimited
Official bulk email is an efficient tool for disseminating information to a wide audience. Its inherent efficiency, captive audience, and trust provide a dangerous attack vector for adversaries utilizing fraudulent email. Digital authentication can provide a layer of defense to official bulk email that, combined with other defensive countermeasures, will greatly reduce its vulnerabilities. The Department of Defense mandates that official emails, which contain hyperlinks, attachments, or instructions to recipients, must contain a digital signature, authenticating the source of the email, and ensuring the integrity of its contents. This policy, though used at some military installations, is not being applied to official bulk email at others due to administrative roadblocks in obtaining role-based certificates, and implementing an authentication policy with legacy email systems. This thesis identified administrative roadblocks in deploying digital authentication solutions within the Department of Defense, explored different technology options of a digital authentication solution for official bulk email, created a proof of concept solution using a Python proxy server and S/MIME, and looked at the most popular mail user agents to see how they interpret S/MIME digital signatures. Applying digital authentication to official bulk email will close a potentially critical vulnerability in the defense of DoD networks.

This thesis examines the dry bulk sector of the shipping industry. We begin by analysing the relation between second-hand vessel prices, net earnings, and holding period returns. Specifically, we provide strong statistical evidence that almost the entire volatility of shipping earnings yields can be attributed to variation in expected net earnings growth; almost none to expected returns variation and almost none to varying expectations about the terminal earnings yield. According to our results, earnings yields are negatively and significantly related to future net earnings growth. Furthermore, we find no consistent, strong statistical evidence supporting the existence of time-varying risk premia in the valuation of dry bulk vessels. Accordingly, we integrate the examination of the second-hand market by incorporating in the analysis the trading activity related to dry bulk vessels. For this purpose, we develop a heterogeneous expectations asset pricing model that can account for the actual behaviour of vessel prices and the positive correlation between net earnings, vessel prices, and second-hand vessel transactions. The proposed economy consists of two agent types who form heterogeneous expectations about future net earnings and at the same time under(over)estimate the future demand responses of their competitors. Formal estimation of the model suggests that the average investor expectations in the second-hand market for ships must be “near-rational”. In particular, the investor population must consist of a very large fraction of agents with totally – or very close to – rational beliefs while the remaining ones must hold highly extrapolative beliefs; thus, there must exist significant heterogeneity of beliefs in the market. Having concluded the analysis of the second-hand physical shipping market we turn to the derivative market for Forward Freight Agreements (FFAs) related to the dry bulk shipping sector. Accordingly, we illustrate formally that the bulk of volatility in the FFA basis can be attributed to expectations about future physical market conditions rather than expectations about future risk premia. Despite this finding, though, we document the existence of a bias in the FFA rates in the form of “contango” but also of both a strong momentum effect and significant predictability of risk premia by price-based signals and economic variables reflecting physical market conditions. The evidence of bias is further supported by the results of three econometric tests which suggest rejection of the unbiased expectations hypothesis. Finally, to justify these findings, we develop a dynamic asset pricing framework that can incorporate both the “hedging pressure” feature and a heterogeneous-beliefs explanation.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California
Modern data acquisition systems can be very time consuming to configure. The most time consuming aspect of configuring a data acquisition system is defining the measurements that the system will collect. Each measurement has to be uniquely identified in the system and the system needs to know what data the measurement will sample. Data acquisition systems are capable of sampling thousands of measurements in a single test flight. If all of the measurements are created by hand, it can take many hours to input all of the required measurements into the data acquisition system's setup software. This process can also be extremely tedious since many measurements are very similar. This paper will examine several possible solutions to the problem of rapidly creating large numbers of data acquisition measurements. If the list of measurements that need to be created already exists in an electronic format then the simplest approach would be to create an importer. The two main ways to import data are XML and comma separated value files. This paper will discuss the advantages and disadvantages of both approaches. In addition to importers, this paper will discuss a system that can be used to create large numbers of similar measurements very quickly. This system is ideally suited to MILSTD- 1553 and ARINC-429 bus data. It exploits the fact that most bus measurements are typically very similar to each other. For example, 1553 measurements typically differ only in terms of the command word and the selected data words. This system allows the user to specify ranges of data words for each command word. It can then create the measurements based on the user specified ranges.

Aurinkokennot ovat laitteita, jotka absorboivat auringon valoa ja muuttavat sen sähköenergiaksi. Tässä työssä käsitellään orgaanisten aurinkokennojen aktiivikerroksen elektroninluovuttajayhdisteitä, ja niiden rakenteita.

Carbonized organic precursors such as wood, shells and some plant seeds are very porous. They are nanostructured and tend to be hard, but have pure mechanical properties as a result of their porosities. An attempt was made to carbonize an organic precursor to produce a bulk material with much less porosity for possible use in structural applications such as reinforcement in metal and polymer matrices. A bulk nanocarbon (BNC) material was synthesized using high energy ball milling and the carbonization of corn cob. Corn cob was mechanically milled for up to 20 hours by applying high energy ball milling to produce the milled powder. The milled powder was cold-compacted and carbonized at up to 1500°C to fabricate the BNC material. The material revealed both micro and nano-porosities; the porosities decreased with carbonizing temperature and hold time. Micropores were mostly closed for samples carbonized above 1300oC, whereas they formed interconnected network at lower carbonization temperatures. BNC has a young's modulus of 120 GPa, about ten times that of extruded graphite.
Master of Science
Wood, shells, and plant seeds are examples of organic precursors. When organic precursors are carbonized, they can become very porous, nanostructured, and hard, but deliver pure mechanical properties because of their porosities. A selected organic precursor was carbonized, in an attempt, to produce a bulk material with much less porosity for possible use in structural applications such as reinforcement in metal and polymer matrices. A bulk nanocarbon (BNC) material was made using high energy ball milling and the carbonization of corn cob (the selected organic precursor). This bulk material revealed both micro and nano-porosities, and a young's modulus of 120 GPa, about ten times that of extruded graphite.

Thesis (M.S. in Computer Science)--Naval Postgraduate School, March 2009.
Thesis Advisor(s): Garfinkel, Simson L. "March 2009." Description based on title screen as viewed on April 24, 2009. Author(s) subject terms: Digital Authentication, S/MIME, Official bulk email, phishing. Includes bibliographical references (p. 55-57). Also available in print.

Spinning-disc Reactor (SDR) pilot studies show that the rate of free-radical bulk or near-bulk polymerisation, Rp, is increased without an increase in temperature, and subsequently polymers of high molecular weight (MW) and narrow molecular weight distribution (MDW) are seen.

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Repairing on composite resin restorations can be a conservative alternative to remedy restoration failures as it preserves parts of the tooth that would normally be removed during a complete exchange. The objective of this work was to evaluate the bond strength of post-repair and aging composite resins in different solutions (distilled water, 75% water-alcohol and 0.02N nitric acid). Five composite resins were used, being a conventional resin (Z350) and four bulk fill Filtek Bulk fill (FBF), Filtek Bulk Fill Flow (FBFF), Surefill SDR Flow (SURE) and Opus Bulk Fill Flow (OPUS). Specimens 2x2x5 mm were prepared in prefabricated silicone molds and aged for 30 days, after which the resins were treated with a surface treatment and soon after the repair, becoming a CP with 2x2x10mm. The repairs were performed in the same silicone mold by combining all the resins in the sample, forming 75 groups (n = 10), and immersed again for 30 days in the evaluated solutions. After, the CPs were submitted to the tensile test with the machine DL-200 MF - Emic DL line. The mean values obtained for each CP were submitted to the Kruskall-Wallis test, followed by Dunn's post-test (p <0.05). According to the experimental methodology for Z350 aged in distilled water, the repairs made with the Z350 itself (5.82 + 2.10) and the FBFF (5.88+3.06) showed no statistical differences. For the repairs between FBF (7.44 + 1.68) and OPUS (7.25 + 2.85) there were no statistically significant differences, however, they were higher than SURE (3.59 + 1.57). In 75% water/alcohol solution, all repairs made on the Z350 base were statistically similar. For the 0.02N nitric acid solution and for the Z350 base, the repairs with FBFF (4.37+1.08) and SURE (4.44+1.29) showed no differences between themselves and with FBF (3,37+0.54) and OPUS (5.43+1.21), but were higher than those with Z350 (2.27 + 0.61). When the base was FBF and the solution to distilled water, repairs with FBF (4.90 + 1.98), FBFF (5.50 + 1.56) and SURE (6.08 + 2.01) did not show Differences. Repairs with OPUS were higher (7.32 + 1.74) compared to Z350 (3.82 + 1.85). FBF as a base in the 75% water / alcohol solution and 0.02N nitric acid the repairs showed no differences between them. For the FBFF base in the distilled water, the repair with the same FBFF (7.64 + 2.86) showed no differences with the other resins. (3,63 + 2,86), SURE (7,25 + 3,03), and OPUS (6,83 + 2,40) compared to the bulk fill flow resins, FBFF (7,64 + 2,86). Which did not show significant differences between them. For the 75% water / alcohol solution there were no significant differences between the repairs compared to each other. For the 0.02N nitric acid solution, there were no statistically significant differences when comparing the Z350, FBFF and OPUS resins with each other. The results were higher for SURE (9.93+3.91) when compared to FBF (5.67+1.83) both as repair. For the SURE base in the distilled water solution, there were no significant differences between all the repairs. In the 75% water / alcohol solution, for repairs with Z350 (1.55+067), FBF (2.24+1.09), SURE (2.37+0.85) and OPUS (2.13+0.75) were not different from each other, but were better than the FBFF (2.76+0.73), and the FBF (2.24+1.09) was not different when compared to the others. In the 0.02N nitric acid solution, all repairs were statistically similar to each other. For OPUS as a base, in the distilled water solution, repairs with SURE (3.20+0.67) and OPUS (4.09+1.12) were similar to each other. The Z350 (2.83+1.36) and FBF (2.73+0.94) showed no significant differences among themselves, but compared to the FBFF resin (5.04+1.27) had worse results than this. In 75% water/ethanol solution and nitric acid there were no statistically significant differences between the resins used in the repair. According to the results obtained, it was possible to verify that, in the majority of the comparisons made among the composite resins evaluated in this study, the nanoparticulate resin presented the worst values of bond strength when used as repair. On the other hand, the bulk fill composites presented the best behavior when used as repair.
Os reparos em restaurações em resina composta podem ser uma alternativa conservadora para solucionar falhas de adaptação das mesmas, pois preserva partes do dente que normalmente seriam removidas durante uma troca completa. O objetivo desse trabalho foi avaliar a resistência de união das resinas compostas pós-reparo e envelhecimento em diferentes soluções (água destilada, água/álcool 75% e ácido nítrico 0,02N). Foram utilizadas cinco resinas compostas, sendo uma resina nanoparticulada (Z350) e quatro resinas bulk fill (Filtek Bulk fill (FBF), Filtek Bulk Fill Flow (FBFF), Surefill SDR Flow (SURE) e Opus Bulk Fill Flow (OPUS)). Foram confeccionados corpos de prova (CP) de 2x2x5 mm em molde de silicone pré-fabricado e envelhecidas por 30 dias, após esse período as resinas receberam o tratamento de superfície e logo após o reparo, tornando-se um CP com 2x2x10mm. Os reparos foram realizados no mesmo molde de silicone através da combinação entre todas as resinas da amostra, formando 75 grupos (n=10), sendo imersas novamente por 30 dias nas soluções avaliadas. Após, os CP foram submetidos ao teste de tração com a máquina DL-200 MF – Emic linha DL. Os valores médios obtidos para cada CP foram submetidos ao teste de Kruskall Wallis, seguido do pós-teste de Dunn, (p < 0,05). De acordo com a metodologia experimental para a base de Z350 envelhecida em água destilada, os reparos feitos com a própria Z350 (5,82+2,10) e com a FBFF (5,88+3,06) não houve diferenças estatísticas significantes. Para os reparos entre a FBF (7,44+1,68) e OPUS (7,25+2,85) não houve diferenças estatísticas significantes, porém elas foram superiores à SURE (3,59+1,57). Na solução água/álcool 75%, todos os reparos feitos na base Z350 mostraram-se semelhantes estatisticamente. Para a solução de ácido nítrico 0,02N e para a base de Z350, os reparos com a FBFF (4,37 +1.08) e SURE (4,44+1,29) não mostraram diferenças entre si e com as FBF (3,37+0,54) e OPUS (5,43+1,21), mas foram superiores aos reparos com a Z350 (2,27+0,61). Quando a base foi a FBF e a solução a água destilada, os reparos com FBF (4,90+1,98), FBFF (5,50+1,56) e SURE (6,08+2,01) não mostraram diferenças às demais. Reparos com a OPUS (7,32+1,74) foram superiores, comparados à Z350 (3,82+1,85). FBF como base na solução de água/álcool 75% e ácido nítrico 0,02N os reparos não mostraram diferenças entre si. Para a base de FBFF na água destilada, o reparo com a mesma FBFF (7,64+2,86) não mostrou diferenças com as demais resinas. Z350 (3,53+1,55) quando comparada às resinas bulk fill flow, FBFF (7,64+2,86), SURE (7,25+3,03) e OPUS (6,83+2,40), não mostraram diferenças significantes entre si. Para a solução água/álcool 75% não houve diferenças significantes dos reparos comparados entre si. Para a solução de ácido nítrico 0,02N, não houve diferenças estatisticamente significantes quando se comparou as resinas Z350, FBFF e OPUS entre si e as demais. Os resultados foram superiores para a SURE (9,93+3,91) quando se comparou com a FBF (5,67+1,83) ambas como reparo. Para a base SURE na solução de água destilada, não houve diferenças significantes entre todas nos reparos. Na solução de água/álcool 75%, para os reparos com Z350 (1,55+067), FBF (2,24+1,09), SURE (2,37+0,85) e OPUS (2,13+0,75) não houve diferenças entre si, mas foram melhores que a FBFF (2,76+0,73), e a FBF (2,24+1,09) não foi diferente quando comparada às demais. Na solução de ácido nítrico 0,02N, todos os reparos foram estatisticamente semelhantes entre si. Para a OPUS como base, na solução de água destilada, os reparos com a SURE (3,20+0,67) e OPUS (4,09+1,12) foram semelhantes entre si e às demais. A Z350 (2,83+1,36) e FBF (2,73+0,94) não mostraram diferenças significantes entre si, mas comparadas à resina FBFF (5,04+1,27) tiveram piores resultados em relação a esta. Em solução de água/etanol 75% e ácido nítrico não houve diferenças estatisticamente significantes entre as resinas utilizadas no reparo. De acordo com os resultados obtidos foi possível verificar que, na maioria das comparações realizadas entre as resinas compostas avaliadas nesse estudo, a resina composta nanoparticulada apresentou os piores valores de resistência a união quando utilizada como reparo. Já as resinas compostas bulk fill apresentaram na maioria das comparações realizadas o melhor comportamento quando utilizada como reparo.

En aquesta tesi ens centrem en les estructures d'or i la seva activitat catalítica. La tesi discuteix la producció d'epòxid de propè sobre les superfícies d'or, el mecanisme de formació de sistemes monodimensionals de gran interès tecnològic i la modelització de nanopartícules de sistemes reals amb activitat catalítica en processos essencials com l'activació de l'oxigen molecular.
En general, els resultats aporten detalls acurats dels processos estudiats en total concordança amb la bibliografia com, per exemple, que l'epoxidació sobre la superfície d'Au(111) no és el camí més favorable o que el mecanisme de formació de nanofils be determinat per l'augment de coordinació dels àtoms que interaccionen. Igualment s'aclareix on i com succeeix la reacció de dissociació d'O2 sobre les nanopartícules d'or, delimitant la mida de les partícules actives. A més la tesis inclou simulacions microcinètiques per a optimitzar els processos que poden tindre lloc a la industria.
In this thesis we focus on the structures of gold and its catalytic activity. This thesis discusses about the production of propylene epoxide on gold surface, the formation mechanism of mono-dimensional systems with technological interest as well as the modelling of real nanoparticles with catalytic activity on essential processes such as molecular oxygen activation.
In general, the results provide accurate details of the studied processes in agreement with the literature. For instance, that the epoxidation process on Au(111) surface is not the most favourable way; or that the formation mechanism of nanowires is determined by increased coordination of binding atoms. The results also illustrate where and how the reaction of O2 dissociation occurs on gold nanoparticles, delimiting the size of active particles. In addition, the thesis includes microkinetic simulations to optimize the processes that could be in industry.

Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Dr. Farrokh Ayazi; Committee Co-Chair: Dr. F. Levant Degertekin; Committee Member: Dr. Paul Kohl; Committee Member: Dr. Peter Hesketh; Committee Member: Dr. Suresh K. Sitaraman. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Eine der Faustregeln der Kolloid- und Oberflächenphysik ist, dass die meisten Oberflächen geladen sind, wenn sie mit einem Lösungsmittel, normalerweise Wasser, in Kontakt treten. Dies ist zum Beispiel bei ladungsstabilisierten Kolloidalen Suspensionen der Fall, bei denen die Oberfläche der Kolloidteilchen geladen ist (gewöhnlich mit einer Ladung von mehreren Hunderttausend Elementarladungen), oder bei Monoschichten ionischer Tenside, die auf einer Luft-Wasser Grenzfläche sitzen (wobei die wasserliebenden Kopfgruppen durch die Freisetzung von Gegenionen geladen werden), sowie bei Doppelschichten, die geladene phospholipide enthalten (wie Zellmembranen). In dieser Arbeit betrachten wir einige Modellsysteme, die zwar eine vereinfachte Fassung der Realität darstellen, von denen wir aber dennoch erwarten koennen, dass wir mit ihrer Hilfe einige physikalische Eigenschaften realer geladener Systeme (Kolloide und Elektrolyte) einfangen können.
One of the rules-of-thumb of colloid and surface physics is that most surfaces are charged when in contact with a solvent, usually water. This is the case, for instance, in charge-stabilized colloidal suspensions, where the surface of the colloidal particles are charged (usually with a charge of hundreds to thousands of e, the elementary charge), monolayers of ionic surfactants sitting at an air-water interface (where the water-loving head groups become charged by releasing counterions), or bilayers containing charged phospholipids (as cell membranes). In this work, we look at some model-systems that, although being a simplified version of reality, are expected to capture some of the physical properties of real charged systems (colloids and electrolytes).

We initially study the simple double layer, composed by a charged wall in the presence of its counterions. The charges at the wall are smeared out and the dielectric constant is the same everywhere. The Poisson-Boltzmann (PB) approach gives asymptotically exact counterion density profiles around charged objects in the weak-coupling limit of systems with low-valent counterions, surfaces with low charge density and high temperature (or small Bjerrum length). Using Monte Carlo simulations, we obtain the profiles around the charged wall and compare it with both Poisson-Boltzmann (in the low coupling limit) and the novel strong coupling (SC) theory in the opposite limit of high couplings. In the latter limit, the simulations show that the SC leads in fact to asymptotically correct density profiles. We also compare the Monte Carlo data with previously calculated corrections to the Poisson-Boltzmann theory. We also discuss in detail the methods used to perform the computer simulations.

After studying the simple double layer in detail, we introduce a dielectric jump at the charged wall and investigate its effect on the counterion density distribution. As we will show, the Poisson-Boltzmann description of the double layer remains a good approximation at low coupling values, while the strong coupling theory is shown to lead to the correct density profiles close to the wall (and at all couplings). For very large couplings, only systems where the difference between the dielectric constants of the wall and of the solvent is small are shown to be well described by SC.

Another experimentally relevant modification to the simple double layer is to make the charges at the plane discrete.
The counterions are still assumed to be point-like, but we constraint the distance of approach between ions in the plane and counterions to a minimum distance D. The ratio between D and the distance between neighboring ions in the plane is, as we will see, one of the important quantities in determining the influence of the discrete nature of the charges at the wall over the density profiles. Another parameter that plays an important role, as in the previous case, is the coupling as we will demonstrate, systems with higher coupling are more subject to discretization effects than systems with low coupling parameter.

After studying the isolated double layer, we look at the interaction between two double layers. The system is composed by two equally charged walls at distance d, with the counterions confined between them. The charge at the walls is smeared out and the dielectric constant is the same everywhere. Using Monte-Carlo simulations we obtain the inter-plate pressure in the global parameter space, and the pressure is shown to be negative (attraction) at certain conditions. The simulations also show that the equilibrium plate separation (where the pressure changes from attractive to repulsive) exhibits a novel unbinding transition. We compare the Monte Carlo results with the strong-coupling theory, which is shown to describe well the bound states of systems with moderate and high couplings. The regime where the two walls are very close to each other is also shown to be well described by the SC theory.

Finally, Using a field-theoretic approach, we derive the exact low-density ("virial") expansion of a binary mixture of positively and negatively charged hard spheres (two-component hard-core plasma, TCPHC). The free energy obtained is valid for systems where the diameters d_+ and d_- and the charge valences q_+ and q_- of positive and negative ions are unconstrained, i.e., the same expression can be used to treat dilute salt solutions (where typically d_+ ~ d_- and q_+ ~ q_-) as well as colloidal suspensions (where the difference in size and valence between macroions and counterions can be very large). We also discuss some applications of our results.

This work summarizes several studies that all concern cellulose ethers of the types methylcellulose (MC) hydroxypropylmethylcellulose (HPMC) and ethyl(hydroxyethyl)cellulose (EHEC). They share the feature of negative temperature response, as they are soluble in water at room temperature but phase separate and sometimes form gels at high temperatures. The different types of viscosity transitions occurring in these three cellulose ethers are well-known. However, earlier studies have not solved the problem of why both HPMC and EHEC, as the temperature increases, exhibit a viscosity decrease just before the viscosity increases, whereas MC only has one transition temperature where the viscosity increases. With our investigations we have aimed to compare the effect of temperature on bulk solutions and on adsorbed layers of the different polymers using a range of techniques. Light scattering and cryo transmission electron microscopy (cryo-TEM) was employed to study aggregation of MC, HPMC and EHEC in solution. The solvent quality of water is reduced for all three polymers in solution as the temperature increases, and this infers an onset of aggregation at a certain temperature. The aggregation rate follows the order EHEC > HPMC > MC. Cryo-TEM pictures of solutions frozen from high temperatures showed closely packed fibrils forming dense networks in MC solution. Some fibrils were also found in HPMC solution above the transition temperature, but they did not interconnect readily. This is explained by the bulky and hydrophilic hydroxypropyl groups attached to HPMC. EHEC has similar substituents, while MC only has short and hydrophobic methyl groups attached to the main chain. An amphiphilic liquid, diethyleneglycolmonobutylether (BDG) was used as an additive to change the properties of MC solutions in water. With 10 wt% BDG added, the effect was similar in viscosity and light scattering measurements as well as cryo-TEM pictures, inducing a temperature response resembling that of HPMC in pure water. 5 wt% of BDG was enough to change the aggregation type and induce a transition temperature with viscosity decrease. The effect of the additive is rationalized by BDG acting as a hydrophobic and bulky substituent in MC, similar to the large substituents in HPMC and EHEC. Two instruments, a quartz crystal microbalance with dissipation (QCM-D) and an ellipsometer, were used in parallel to determine the changes with temperature on an adsorbed layer of MC and HPMC on silica kept in water and in polymer solution. The silica needed to be hydrophobized for significant adsorption to take place. Adsorption was similar for both polymers at low temperatures, whereas a sharp transition in several layer properties occurred for HPMC, but not for MC, close to the solution viscosity transition temperature. Atomic force microscopy (AFM) was used to measure attractive and repulsive forces and also friction forces between MC layers in polymer solution. The small changes in normal forces with temperature infer that the hydrophobic groups in MC are mostly depleted from the surface. The surface–polymer interactions increase with increasing temperature and the layer becomes more cohesive, which induces a higher load bearing capacity and lower friction when measured at high loads. AFM imaging was employed to obtain the height distribution in MC adsorbed layers. These images indicate that fibril-like structures were formed at a lower temperature in the surface layer than in bulk solution. The different preferences for adsorption and for aggregation in MC and HPMC above the solution transition temperatures are explained by the fibril formation in MC shielding hydrophobic parts of the polymer from the solution, and thus counteracting adsorption, but also fast aggregation. The viscosity decrease in HPMC and EHEC is conferred to intra-chain contraction and aggregation into less extended structures.

QC 20120523

The minimum spacing of a plasma waveguide was calculated and applied to the formation of periodic nanocracks. The minimum spacing decreased with decreasing plasma frequency but was found to have limited effect on the spacing of the nanocracks. An extension to a standard Finite-Difference Time-Domain method was created to include nonlinear processes and the dynamic build up of the electron plasma. The ionized area produced in the simulation agrees with experiment. The existence of a self-limited absorption effect on a Gaussian pulse in time was verified in the simulations. The region was elongated along the direction parallel to the polarization of the light. The multiphoton absorption was found to be the main cause of the distinct shape of the damaged area. Plasma dispersion and self-focusing create larger electron densities and a shift in the location of the electron density peak, but did not affect the general shape.