Flow injection systems have great potential for sample handling and analysis in process analytical chemistry. The flexibility and versatility of flow injection manifolds can he utilized in specific applications of sample conditioning and analysis. An overview of various flow injection methods, including flow reversals, double injection, and sequential injection is given, as well as different clean-up methods, such as gas diffusion, solid phase extraction, dialysis, and solvent extraction. Calibration techniques, such as single standard and multivariate calibration are also discussed. In addition, different aspects of process analytical chemistry, in particular sampling and sample handling, are discussed. The papers in this thesis describe a number of flow systems, where gradient-, gas diffusion-, and solid phase extraction- methodologies are applied, all of which have potential use in process analytical chemistry. Paper I is focused on multicomponent analysis of mixtures of organic acids by mathematically extracting information from complex spectra. The selectivity is improved by generating pH-gradients in the flow system. In paper II, the methodology of sensor injection is described and electrochemical and spectroscopic sensors are implemented in a sequential injection system. The method is illustrated by using pH sensors and a glucose electrode. Ammonia and ammonium ions are determined on-line to a bioprocess by gas diffusion in paper III. The benefit of frequent re-calibrations and in-line cleaning sequences are demonstrated. Finally a method for on-line determination of o-diphenols in the kraft process has been developed (paper IV). The o-diphenols are isolated from black liquor samples by solid phase extraction and thereafter transferred to a high performance liquid chromatography system for separation and quantification. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1996, Härtill 4 uppsatser</p> / digitalisering@umu

abstract: E-Mail header injection vulnerability is a class of vulnerability that can occur in web applications that use user input to construct e-mail messages. E-Mail injection is possible when the mailing script fails to check for the presence of e-mail headers in user input (either form fields or URL parameters). The vulnerability exists in the reference implementation of the built-in “mail” functionality in popular languages like PHP, Java, Python, and Ruby. With the proper injection string, this vulnerability can be exploited to inject additional headers and/or modify existing headers in an e-mail message, allowing an attacker to completely alter the content of the e-mail. This thesis develops a scalable mechanism to automatically detect E-Mail Header Injection vulnerability and uses this mechanism to quantify the prevalence of E- Mail Header Injection vulnerabilities on the Internet. Using a black-box testing approach, the system crawled 21,675,680 URLs to find URLs which contained form fields. 6,794,917 such forms were found by the system, of which 1,132,157 forms contained e-mail fields. The system used this data feed to discern the forms that could be fuzzed with malicious payloads. Amongst the 934,016 forms tested, 52,724 forms were found to be injectable with more malicious payloads. The system tested 46,156 of these and was able to find 496 vulnerable URLs across 222 domains, which proves that the threat is widespread and deserves future research attention. / Dissertation/Thesis / Masters Thesis Computer Science 2016

Please read the abstract in the front section of this document / Dissertation (MSc (Chemistry))--University of Pretoria, 2005. / Chemistry / unrestricted

The aim of my graduation theses is to work up the literature search of polymer processing. To give a short summary of their structure, characteristic and fabrication technique. Then to make a structural design of injection mold for producing the scheduled aim and motivate this design with requisite calculation for construction of the tool, a choice of injection machine and rundown of injection cycle. At the end of my work is this aim economically reviewed and compared with alternative form of structural design.

Diploma thesis which is developed for the master’s degree program (M2I – K Mechanical engineering) presents a proposal solution for production technology plastic car headlins parts from polymer material PBT GF30. Literature review summarizes the findings of thermoplastic injection technology and the structural design possibility of injection molds. The paper examined two variants of the running system, which are suitable for production of injection molding components. Finaly, after technical - economic assessment, we came to the conclusion that the better option is to use the hot runner system. In the practical part is the specified product modeled by the help of 3D software and the injection mold was designed. The design was implemented by CATIA V5 R20. For the design and manufacture of injection mold were used normality from MEUSBURGER. For the chosen alternative technology of production were made calculations and was selected injection molding machine Electron 75 – 300 from FERROMATIC.

CO2 sequestration is one of the proposed methods for reducing anthropogenic CO2 emissions to the atmosphere and therefore mitigating global climate change. Few studies on storing CO2 in an aquifer have been conducted on a regional scale. This study offers a conceptual approach to increasing the storage efficiency of CO2 injection in saline formations and investigates what an actual CO2 storage project might entail using field data for the Woodbine aquifer in East Texas. The study considers three aquifer management strategies for injecting CO2 emissions from nearby coal-fired power plants into the Woodbine aquifer. The aquifer management strategies studied are bulk CO2 injection, and two CO2-brine displacement strategies. A conceptual model performed with homogeneous and average reservoir properties reveals that bulk injection of CO2 pressurizes the aquifer, has a storage efficiency of 0.46% and can only last for 20 years without risk of fracturing the CO2 injection wells. The CO2-brine displacement strategy can continue injecting CO2 for as many as 240 years until CO2 begins to break through in the production wells. This offers 12 times greater CO2 storage efficiency than the bulk injection strategy. A full field simulation with a geological model based on existing aquifer data validates the storage capacity claims made by the conceptual model. A key feature in the geological model is the Mexia-Talco fault system that serves as a likely boundary between the saline aquifer region suitable for CO2 storage and an updip fresh water region. Simulation results show that CO2 does not leak into the fresh water region of the iv aquifer after 1000 years of monitoring if the faults have zero transmissibility, but a negligible volume of brine eventually gets through the mostly sealing fault system as pressure across the faults slowly equilibrates during the monitoring period. However, for fault transmissibilities of 0.1 and 1, both brine and CO2 leak into the fresh water aquifer in increasing amounts for both bulk injection and CO2-brine displacement strategies. In addition, brine production wells draw some fresh water into the saline aquifer if the Mexia-Talco fault system is not sealing. A CO2 storage project in the Woodbine aquifer would impact as many as 15 counties with high-pressure CO2 pipelines stretching as long as 875 km from the CO2 source to the injection site. The required percentage of power plant energy capacity was 7.43% for bulk injection, 7.9% for the external brine disposal case, and 10.2% for the internal saturated brine injection case. The estimated total cost was $0.00132–$0.00146/kWh for the bulk injection, $0.00191–$0.00211/kWh for the external brine disposal case, and $0.0019–$0.00209/kWh for the internal saturated brine injection case.

Flow injection analysis offers distinct advantages in reproducibility, flexibility, sample throughput and cost performance. Since it was introduced in 1975, there are more than 10 000 publications to date. The present study focuses on the development of process analysers for the determination of nitrogen compounds (namely, nitrate, nitrite and protein), nickel, and phosphate in various combination in samples originating from various fields, such as foodstuffs, water, and fertilisers. Nitrite is potentially unstable; it decomposes with time under acidic medium with an increase in decomposition rate as the concentration of acid increases. Raman spectroscopy was employed as a means of determining the rate of decomposition of nitrite in solutions at various pH values. A simple method for the determination of nitrite in foodstuffs by flow injection analysis (FIA) is described. The foodstuffs containing nitrite are digested in a microwave oven and then treated with 1 moℓ/Q NH4CI solution at pH 9. The simultaneous determination of nitrate and nitrite in foodstuffs and water was also studied. Cadmium (coarse powder) was used to reduce nitrate to nitrite. The effect of pH, length of reductor column, and various types of cadmium reductor on the yield of nitrite are investigated. The flow injection method was developed for the spectrophotometric determination of nickel in cured meat. Dimethylglyoxime (DMG) in acetate buffer at pH 6.4 nickel forms a red complex which is measured at 475 nm. The effects of chemical and physical parameters in flow injection analysis were studied. A new bienzymatic amperometric sensor is proposed for the assay of proteins in milk. The sensor is based on two enzymes, namely, carboxypeptidases A and L-amino acid oxidase. The use of flow injection analysis and Raman spectroscopy for the determination of phosphate in foodstuffs and fertilisers, is also compared in this study. / Thesis (PhD (Chemistry))--University of Pretoria, 2007. / Chemistry / unrestricted

This thesis describes the optimalization of technological parameters during commissioning of injection mold manufacturing. In the introduction, there is general literary studies of plastics, injection molds, injection holding machine, injection holding technology and their effect on quality. The practical part includes an analysis of current state, calculation of injection parameters, moldflow analysis and sampling on the machine. Finally, there is choice of optimal injection holding parameters, design of workplace and technical-economic evaluation.

Cette thèse s'intéresse à la sécurité des programmes embarqués face aux attaques par injection de fautes. La prolifération des composants embarqués et la simplicité de mise en œuvre des attaques rendent impérieuse l'élaboration de contre-mesures.Un modèle de fautes par l'expérimentation basé sur des attaques par impulsion électromagnétique a été élaboré. Les résultats expérimentaux ont montré que les fautes réalisées étaient dues à la corruption des transferts sur les bus entre la mémoire Flash et le pipeline du processeur. Ces fautes permettent de réaliser des remplacements ou des saut d'instructions ainsi que des modifications de données chargées depuis la mémoire Flash. Le remplacement d'une instruction par une autre bien spécifique est très difficile à contrôler ; par contre, le saut d'une instruction ciblée a été observé fréquemment, est plus facilement réalisable, et permet de nombreuses attaques simples. Une contre-mesure empêchant ces attaques par saut d'instruction, en remplaçant chaque instruction par une séquence d'instructions, a été construite et vérifiée formellement à l'aide d'outils de model-checking. Cette contre-mesure ne protège cependant pas les chargements de données depuis la mémoire Flash. Elle peut néanmoins être combinée avec une autre contre-mesure au niveau assembleur qui réalise une détection de fautes. Plusieurs expérimentations de ces contre-mesures ont été réalisées, sur des instructions isolées et sur des codes complexes issus d'une implémentation de FreeRTOS. La contre-mesure proposée se révèle être un très bon complément pour cette contre-mesure de détection et permet d'en corriger certains défauts. / This thesis focuses on the security of embedded programs against fault injection attacks. Due to the spreadings of embedded systems in our common life, development of countermeasures is important.First, a fault model based on practical experiments with a pulsed electromagnetic fault injection technique has been built. The experimental results show that the injected faults were due to the corruption of the bus transfers between the Flash memory and the processor’s pipeline. Such faults enable to perform instruction replacements, instruction skips or to corrupt some data transfers from the Flash memory.Although replacing an instruction with another very specific one is very difficult to control, skipping an instruction seems much easier to perform in practice and has been observed very frequently. Furthermore many simple attacks can carried out with an instruction skip. A countermeasure that prevents such instruction skip attacks has been designed and formally verified with model-checking tool. The countermeasure replaces each instruction by a sequence of instructions. However, this countermeasure does not protect the data loads from the Flash memory. To do this, it can be combined with another assembly-level countermeasure that performs a fault detection. A first experimental test of these two countermeasures has been achieved, both on isolated instructions and complex codes from a FreeRTOS implementation. The proposed countermeasure appears to be a good complement for this detection countermeasure and allows to correct some of its flaws.

Published Article / The paper presents a critical review of the techniques that are used to cool plastic injection moulds. It examines research on cooling of injection moulds by conventional cooling, the benefits and the limitations of the method. It compares the deployment mechanisms that have been proposed by various researchers. It also examines how the various mechanisms affect the plastic cooling rate and the overall heat transfer performance of the mould and how the various deployments affect the stress distribution of the mould and mould durability. The paper also presents the possibilities that have been presented by rapid prototyping. It discusses the development of conformal cooling as an alternative to conventional cooling. It presents the state of the art on the method. The paper presents the deficiencies in the current theories on conformal cooling and suggests areas that require further work in order to fully exploit the technique.