There is problem that every company has its own customer portal. This problem can be solved by creating a platform that gathers all customers’ portals in one place. For such platform, it is required a web API protocol that is fast, secure and has capacity for many users. Consequently, a survey of various web API protocols has been made by testing their performance and security. The task was to find out which web API protocol offered high security as well as high performance in terms of response time both at low and high load. This included an investigation of previous work to find out if certain protocols could be ruled out. During the work, the platform’s backend was also developed, which needed to implement chosen web API protocols that would later be tested. The performed tests measured the APIs’ connection time and their response time with and without load. The results were analyzed and showed that the protocols had both pros and cons. Finally, a protocol was chosen that was suitable for the platform because it offered high security and fast connection. In addition, the server was not affected negatively by the number of connections. Reactive REST was the web API protocol chosen for this platform. / Det finns ett problem i dagens samhälle gällande att varje företag har sin egen kundportal. Detta problem kan lösas genom att skapa en plattform som samlar alla kundportaler på samma plats. För en sådan plattform krävs det ett web API protokoll som är snabb, säker och har kapacitet för många användare. Därför har en undersökning om olika web API protokolls prestanda samt säkerhetstester gjorts. Arbetet gick ut på att ta reda på vilket web API protokoll som erbjuder hög säkerhet och hög prestanda i form av svarstid både vid låg och hög belastning. Det ingick också i arbetet att göra en undersökning av tidigare arbeten för att ta reda på om eventuella protokoll kunde uteslutas. Under arbetet utvecklades också plattformens backend som implementerade de olika web API protokollen för att sedan kunna utföra tester på dessa. Testerna som utfördes var svarstid både med och utan belastning, uppkopplingstid samt belastning. Resultaten analyserades och visade att protokollen hade både för- och nackdelar. Avslutningsvis valdes ett protokoll som var lämpad för plattformen eftersom den hade hög säkerhet samt snabbast uppkopplingstid. Dessutom påverkades inte servern negativt av antalet uppkopplingar. Reactive REST valdes som web API protokoll för denna plattform.

In this study, the application of bipolar electrocoagulation (EC) with iron electrode has been assessed for color removal of simulated wastewater containing Reactive Red 195. The influence of initial pH, sodium sulfate concentration, initial dye concentration, electrolysis time, and electric current were examined. The optimum operational parameters were found to be pH =11, concentration of dye = 50 mg L-1, sodium sulfate concentration = 1200 mg L-1, electrolysis time = 5 min and electric current = 4 A. In such condition, color removal efficiency achieved over 99%. This result indicates that EC can be used as an efficient and “green” method for color removal from reactive dye solution. / Trong nghiên cứu này, quá trình khử màu nhuộm hoạt tính (Reactive Red 195) được khảo sát bằng hệ thống keo tụ điện hóa điện cực kép, với vật liệu sắt. Các yếu tố ảnh hưởng đến quá trình khử màu như pH, nồng độ màu nhuộm, nồng độ muối Na2SO4, thời gian phản ứng và cường độ dòng được lựa chọn nghiên cứu. Kết quả cho thấy hệ thống điện hóa trên loại gần như hoàn toàn màu nhuộm với hiệu suất đạt trên 99 % tại pH 11, nồng độ màu 50 mgL-1 và nống độ muối Na2SO4 1200 mgL-1 trong khoảng thời gian 5phút. Kết quả trên cho thấy keo tụ điện hóa có thể xem là một phương pháp xử lý hiệu quả và “xanh” trong việc loại bỏ hoàn toàn màu từ nước thải nhuộm hoạt tính.

Wastewater from the textile industry is difficult to treat effectively due to the prevalent use and wide variety of synthetic dyes that are resistant to conventional treatment methods. White-rot fungi, such as Trametes versicolor, have been found to be effective in decolorizing many of these synthetic dyes and current research is focusing on their application to wastewater treatment. Although numerous studies have been conducted on the ability of both living and nonliving Trametes versicolor to separately decolorize textile dyes, no studies were found to have investigated the use of a mixture of live and dead fungus for decolorization. This study explored potential interactions between live and dead, autoclaved Trametes versicolor biomass in a mixed system by utilizing a series of batch tests with two structurally different synthetic textile dyes. Samples were analyzed by spectrophotometer and compared with controls to determine the effect of any interactions on decolorization. The results of this study indicate that an interaction between living and nonliving biomass occurred that affected the specific dye removal for both Reactive Blue 19, an anthraquinone textile dye, and Reactive Orange 16, an azo textile dye. This interaction was seen to improve the specific dye removal during the first 10-46 hours of experimentation but then diminish the specific dye removal after this period. This effect could be due to hydrophobins, which are surface-active proteins excreted by live fungi that may alter hydrophobicity. Additionally, the presence of adsorptive dead biomass could affect dye contact with degrading enzymes released from the live fungus. By expanding current knowledge of the interactions that take place in a fungal bioreactor and their effect on textile dye decolorization, this research aims to inspire more effective and less costly bioreactor designs for the treatment of textile wastewater.

The synthesis of a number of alkyl esters such as methyl lactate, methyl decanoate, and ethyl benzoate via esterification in a reactive distillation is quite challenging. It is due to the complexity in the thermodynamic behaviour of the chemical species in the reaction mixture in addition to the difficulty of keeping the reactants together in the reaction section. One of the reactants (in these esterification reactions) having the lowest boiling point can separate from the other reactant as the distillation continues. This can result in a significant drop in the reaction conversion in a conventional reactive distillation whether it is a batch or a continuous column. To overcome this challenge, new different types of batch reactive distillation column configurations: (1) integrated conventional (2) semi-batch (3) integrated semi-batch (4) integrated dividing-wall batch distillation columns have been proposed here. Four esterification reaction schemes such as (a) esterification of lactic acid (b) esterification of decanoic acid (c) esterification of benzoic acid (d) esterification of acetic acid are investigated here. A detailed dynamic model based on mass, energy balances, chemical reaction, and rigorous thermodynamic (chemical and physical) properties is considered and incorporated in the optimisation framework within gPROMS (general PROcess Modelling System) software. It is found that for the methyl lactate system, the i-SBD operation outperforms the classical batch operations (CBD or SBD columns) to satisfy the product constraints. While, for the methyl decanoate system, the i-DWCBD operation outperforms all CBD, DWBD and sr-DWBD configurations by achieving the higher reaction conversion and the maximum product purity. For the ethyl benzoate system, the performance of i-CBD column is superior to the CBD process in terms of product quality, and conversion rate of acid. The CBD process is found to be a more attractive in terms of operating time saving, and annual profit improvement compared to the IBD, and MVD processes for the benzyl acetate system. / The Higher Committee for Education Development in Iraq (HCED)

A bigraph-driven vending machine is implemented. The application is realized as a Spring-based webservice. Actions can be initiated by REST endpoints. The system follows a rule-based architecture, where possible operations are grounded on a rule set. Bigraphical Reactive Systems are used for the specification and execution. The actual state of the application is a bigraph stored in a database, which can be viewed and altered directly in the database. A history of states is kept - the application can be transferred to any prior state. The application can be updated or extended by merely changing the bigraphical database model.:First Part: A system of a vending machine is specified and analyzed using BDSL. This concerns the static and dynamic aspects of the system. Second Part: The analysis results are re-used for the implementation using Bigraph Framework. The application is realized as a webservice that is built using the Spring framework. / Ein bigraph-gesteuerter Verkaufsautomat wird implementiert. Die Anwendung ist als Spring-basierter Webservice realisiert. Aktionen können über REST-Endpunkte initiiert werden. Das System folgt einer regelbasierten Architektur, bei der die möglichen Operationen auf einem Regelsatz beruhen. Für die Spezifikation und Ausführung werden Bigraphical Reactive Systems verwendet. Der aktuelle Zustand der Anwendung ist ein in einer Datenbank gespeicherter Bigraph, der direkt in der Datenbank eingesehen und verändert werden kann. Es wird eine Historie der Zustände geführt - die Anwendung kann in einen beliebigen früheren Zustand überführt werden. Die Anwendung kann aktualisiert oder erweitert werden, indem lediglich das bigraphische Datenbankmodell geändert wird.:First Part: A system of a vending machine is specified and analyzed using BDSL. This concerns the static and dynamic aspects of the system. Second Part: The analysis results are re-used for the implementation using Bigraph Framework. The application is realized as a webservice that is built using the Spring framework.

Doctor of Philosophy / Department of Electrical and Computer Engineering / Shelli K. Starrett / Monitoring and control of modern power systems have become very complex tasks due to the interconnection of power grids. These large-scale power grids confront system operators with a huge set of system inputs and control parameters. This work develops and compares intelligent systems-based algorithms which may be considered by power system operators or planners to help manage, process, and evaluate large amounts of data due to varying conditions within the system. The methods can be used to provide assistance in making operational control and planning decisions for the system in a timely manner. The effectiveness of the proposed algorithms is tested and validated on four different power systems. First, Artificial Neural Network (ANN) models are developed and compared for two different voltage collapse indices and utilizing two different-sized sets of inputs. The ANNs monitor and evaluate the voltage profile of a system and generate intelligent conclusions regarding the status of the system from a voltage stability perspective. A feature reduction technique, based on the analysis of generated data, is used to decrease the number of inputs fed to the ANN, decreasing the number of physical quantities that need to be measured. The major contribution of this work is the development of four different algorithms to control the VAR resources in a system. Four different objectives were also considered in this part of the work, namely: minimization of the number of control changes needed, minimization of the system power losses, minimization of the system's voltage deviations, and consideration of the computational time required. Each of the algorithms is iterative in nature and is designed to take advantage of a method of decoupling the load flow Jacobian matrix to decrease the time needed per iteration. The methods use sensitivity information derived from the load flow Jacobian and augmented with equations relating the desired control and dependent variables. The heuristic-sensitivity based method is compared to two GA-based methods using two different objective functions. In addition, a FL algorithm is added to the heuristic-sensitivity algorithm and compared to a PS-based algorithm. The last part of this dissertation presents the use of one of the GA-based algorithms to identify the size of shunt capacitor necessary to enhance the voltage profile of a system. A method is presented for utilizing contingency cases with this algorithm to determine required capacitor size.

Master of Science / Department of Kinesiology / Timothy I. Musch / During exercise aged individuals exhibit endothelial dysfunction and decreased levels of whole-limb blood flow (BF), both of which may be linked mechanistically to age-related increases in reactive oxygen species (ROS). Ascorbic acid (AA) reduces levels of ROS and has been shown to alleviate vascular and hyperemic dysfunction at rest (Jablonski et al., 2007) and during small muscle mass exercise in humans (Kirby et al., 2009). However, the effect of AA on vascular function and BF to individual muscles during whole-body exercise is not known. PURPOSE: To test the hypothesis that a single high-dose infusion of AA would increase BF to the hindlimb musculature of old rats at rest and during treadmill running. METHODS: 18 old (~28 months) Fischer 344 x Brown Norway rats were randomized into rest (n=9) and exercise (n=9) groups. BF to the total hindlimb and individual muscles (28 individual muscles and muscle parts) was evaluated via radiolabeled microspheres before and after intra-arterial AA administration (76 mg/kg in 3 ml heparinized saline, 30 minute infusion) at rest and during submaximal treadmill running (20m/min, 5% grade). Total antioxidant capacity (TAC) and thiobarbituric acid reactive species (TBARS) were measured before and after AA to determine the ability of this specific dose of AA to increase levels of plasma antioxidants and decrease levels of ROS, respectively. RESULTS: At rest: AA increased TAC (~37%, P<0.05) but did not change TBARS (Pre: 6.8±0.7 vs Post: 7.0±1.0 µM, P>0.05). AA decreased total hindlimb BF (Pre: 25±3 vs Post: 16±2 ml/min/100g, P<0.05) and BF to 8 of the 28 muscles that were evaluated. During exercise: TAC was increased (~35%, P<0.05) and TBARS were decreased (Pre: 9.8±2.0 vs Post: 7.0±1.0 µM, P<0.05). However, there was no effect on either total hindlimb BF (Pre: 154±14 vs Post: 162±13, P>0.05) or BF to any of the individual muscles evaluated. CONCLUSIONS: Increased TAC via AA infusion reduces hindlimb muscle BF at rest but had no effect on BF during whole-body dynamic exercise. Thus, even though TBARS decreased, there was no evidence that AA supplementation increases blood flow to the locomotor muscles of old rats during whole-body exercise.

Submitted in fulfillment of the academic requirements for the degree of Master of Technology in Engineering: Chemical Engineering, Durban University of Technology. Durban. South Africa, 2015. / The textile industry consumes large volumes of water and in turn produces substantial quantities of polluted effluents. Approximately 30% of reactive dyes used during the textile processing remain unfixed on fibres and are responsible for the colouration in effluents. Various conventional methods are being used to treat textile effluent. However, the disadvantage of these methods is that total colour removal is not achieved and chemical by-products are introduced from the use of chemicals. The water quality produced therefore does not meet the requirement for textile reuse. Membrane based processes provide interesting possibilities of separating hydrolysed dye stuff and dyeing auxiliaries, thereby reducing colouration and COD content. They can be employed to treat reactive dye bath effluent to recover the salts and water for the purpose of reuse. This study aimed at integrating membrane processes into the reactive dye bath of a textile industry. The objectives were to determine the quality of permeate produced in terms of removal of organics, ascertain its reusability for dyeing, investigate the production rate in terms of permeate fluxes and finally to investigate the cleanability and flux recovery of the membranes. Three effluent samples were chosen for this study based on the dyeing recipe; Light shade, Medium shade and Dark shade. Ultrafiltration (UF) and Nanofiltration (NF) membrane processes were employed to treat the reactive dye bath effluents to recover the salts and water. Investigations were conducted firstly with UF as a pre-treatment to NF. Secondly, evaluations were carried out on the performance of two types of NF membranes (SR90 and NF90) in terms of permeate quality and fluxes for the investigated samples. The effect of cleaning on membrane performance was done. A reusability test was carried out on the permeate samples for dyeing. It was found that the use of UF as a pre-treatment yielded an increase in permeate of 5–25% of the NF fluxes and 90% in organics reduction for all treated samples, hence increasing the water recovery. High rejection of ˃90% by NF90 for COD, TOC and colour were obtained for all the treated samples. SR90 rejection was 80–90% for colour and ˃90% for COD and TOC. Salt recovery for NF90 was 60–90% and for SR90 was 40–50%. The reusability tests carried out showed that permeate recycled from NF90 can be used for any section in the textile industry including the most critical such as dyeing on light shades, while that from SR90 can be used for dyeing dark shades only. It was then concluded that membrane based processes can be integrated into the dye bath of the textile process for the purpose of reuse, thereby saving on the cost of chemicals (salts), reducing fresh water usage and reducing the extent of final effluent treatment.

Blood cells or hemocytes play important roles in immunity. They are a major source of many immune-related molecules such as antibodies in adaptive immunity of vertebrates and prophenoloxidase (proPO) in invertebrates. In the crayfish Pacifastacus leniusculus, the proPO-system has been reported to be an important component of immune responses against microorganisms. In this study, several mutant strains of Aeromonas hydrophila were used to reveal that LPS (lipopolysaccharide) is an important factor for the pathogenicity of A. hydrophila, strongly inducing the proPO system and melanization. This proPO activating system is a multistep process, which has to be tightly controlled to avoid the harmful side effects of toxic intermediates. Many regulating factors have been reported to fine-tune the proPO-system. In this study, the cleavage of caspase-1-like activity was shown to be a novel negative regulator of PO activity in crayfish. Moreover, the fragments obtained by cleavage of proPO by the proPO-activating enzyme and caspase-1-like protein increased bacterial clearance. Thus, the peptides generated also have important biological functions. In addition to being a source of immune proteins, hemocytes also participate in phagocytosis, encapsulation, and nodulation. An infection normally causes a reduction of hemocyte numbers. Consequently, hemocyte homeostasis is important for maintaining appropriate hemocyte numbers in the circulation of the animal. This study shows that the reactive oxygen species level in the anterior proliferation center of crayfish hematopoietic tissue (HPT), together with cell proliferation, was increased during infection. Pl-β-thymosins were proposed to be involved in hemocyte homeostasis by increasing stem cell migration and thus increasing the circulating hemocyte number. Crayfish hemocyte numbers, as well astakine (Ast1 and Ast2) expression in hemocytes and HPT, were previously shown to be under circadian regulation. Here, we show that Ast1, Ast2, and proPO exhibit rhythmic expression in the crayfish brain similarly to their orthologs, prokineticin 1, prokineticin 2 and tyrosinase, respectively, in the zebrafish brain. Tyrosinase expression was detected in zebrafish brain cells while PO-positive cells were identified as hemocytes that had infiltrated into the crayfish brain. Therefore, this information suggests a close relationship between crayfish hemocytes and the crayfish brain as well as vertebrate neurons.

High circulating glucose and non-esterified free fatty acid (NEFA) levels can cause pancreatic β-cell failure. The molecular mechanisms of this β-cell glucolipotoxicity are yet to be established conclusively. In this thesis by exploring mitochondrial energy metabolism in INS-1E insulinoma cells and isolated pancreatic islets, a role of mitochondria in pancreatic β-cell glucolipotoxicity is uncovered. It is reported that prolonged palmitate exposure at high glucose attenuates glucose-stimulated mitochondrial respiration which is coupled to ADP phosphorylation. These mitochondrial defects coincide with an increased level of mitochondrial reactive oxygen species (ROS), impaired glucose-stimulated insulin secretion (GSIS) and decreased cell viability. Palmitoleate, on the other hand, does not affect mitochondrial ROS levels or cell viability and protects against the adverse effects of palmitate on these phenotypes. Interestingly, palmitoleate does not significantly protect against mitochondrial respiratory or insulin secretion defects and in pancreatic islets tends to limit these functions on its own. Furthermore, strong evidence suggests that glucolipotoxic-induced ROS are of a mitochondrial origin and these ROS are somehow linked with NEFA-induced loss in cell viability. To explore the mechanism of glucolipotxic-induced mitochondrial ROS and associated cell loss, uncoupling protein-2 (UCP2) protein levels and activity were probed in NEFA exposed INS-1E cells. It is concluded that UCP2 neither mediates palmitate-induced mitochondrial ROS production and the related cell loss, nor protects against these deleterious effects. Instead, UCP2 dampens palmitoleate protection against palmitate toxicity. Collectively, these data shed important new light on the area of glucolipotoxicity in pancreatic β-cells and provide novel insights into the pathogenesis of Type 2 diabetes.