<p>At the department of Electronic Warfare Assessments at the Swedish Defence Research Agency in Linköping one of the activities is modelling and simulation of the duel between a robot and a target. The aim with this Master's thesis is to develop a simulation model of an hovering helicopter. </p><p>First a theoretical description of the forces and moments acting on an helicopter is given. Then the equations of motion are derived. These equations are simplified to be valid only for a hovering helicopter and the result is a mathematical model. </p><p>The mathematical model is the basis for the design of a regulator, whos task is to bring the helicpoter to equilibrium and keep it hovering. Two different regulators are implemented and tested for several cases when different disturbances are acting on the helicopter. </p><p>The matemathical model and one of the regulators are implemented in a simulation program and the results of the simulations are visualized in a graphical interface.</p>

<p>Denna högskoleavhandling beskriver konstruktionen av ett system vars funktion är att PID-reglera ett linjärställdon kopplad till venturi. Syftet har varit att få fram en reglering på venturin så att förutsättningarna förblir desamma vid mätning av olika temperaturer och lufttryck i en testrigg. Denna testrigg används för att utveckla produkten Varivent som används för att uppfylla högre miljökrav på förbränningsmotorer.</p><p>I arbetet beskriver jag de olika krav som funnits för att bygga det nya systemet, dessa var ingångar, utgångar, mikroprocessor, reglering,</p><p>kommunikation samt övriga krav. Jag diskuterar de svårigheter och möjligheter som är förknippade med kraven och tar även upp de komponenter jag använt samt deras egenskaper. Det svåraste momentet har varit PID-regulatorn som både varit en viktig och en svårlöslig del i konstruktionen av systemet. Slutligen diskuterar jag resultatet där jag, i en analys, kan se att jag kunde underlättat för mig själv med andra angreppsvinklar men att det slutliga resultatet ändå blivit mycket tillfredsställande.</p> / <p>This bachelor thesis describes the design of a unit the function of which is to regulate, using PID controls, a linear mechanical adjusting screw coupled to a variable venturi flow system. The design criteria has been to create, in a test rig, a venturi control system that gives an output that is not affected by changes in either air temperature or pressure. The test rig is used for the development of Varivent, a product used to reduce the environmental impact of the internal combustion engine. In my thesis work I describe the various and necessary elements of the project. These can be termed inputs, outputs, microprocessors, regulators and communicators. I discuss the difficulties and possibilities associated with the design criteria and mention the components used and their different attributes. The most challenging part of the project has been the design of the PID regulator, which, whilst being the heart of the system, has also been the most difficult part of the system to design. Finally I discuss my results where, in an analysis, I see that I could have made things easier for myself had I approached the problems in other ways but that the final result was, despite this, very satisfactory.</p>

<p>Arbetet handlar om hur man med hjälp av LabVIEW 8.0 kan lösa olika uppgifter. Uppgifterna löses med hjälp av ett DAQ-kort. DAQ-kortet gör det möjligt att mata in signaler, som sedan behandlas efter behov i programmet och därefter skickas ut genom DAQ- kortet till olika komponenter som man vill styra. DAQ-kortet klarar att behandla både analoga och digitala signaler. LabVIEW 8.0 och dess historia, DAQ-kortet samt de olika processerna/uppgifter beskrivs mer utförligt i arbetet.</p>

Developments in automotive (particularly hybrid electric vehicles), aerospace, and energy production industries over the recent years have led to expanding research interest in integrated circuit (IC) design toward high-temperature applications. A high-voltage, high-temperature SOI process allows for circuit design to expand into these extreme environment applications. Nearly all electronic devices require a reliable supply voltage capable of operating under various input voltages and load currents. These input voltages and load currents can be either DC or time-varying signals. In this work, a stable supply voltage for embedded circuit functions is generated on chip via a voltage regulator circuit producing a stable 5-V output voltage. Although applications of this voltage regulator are not limited to gate driver circuits, this regulator was developed to meet the demands of a gate driver IC. The voltage regulator must provide reliable output voltage over an input range from 10 V to 30 V, a temperature range of −50 ºC to 200 ºC, and output loads from 0 mA to 200 mA. Additionally, low power stand-by operation is provided to help reduce heat generation and thus lower operating junction temperature. This regulator is based on the LM723 Zener reference voltage regulator which allows stable performance over temperature (provided proper design of the temperature compensation scheme). This circuit topology and the SOI silicon process allow for reliable operation under all application demands. The designed voltage regulator has been successfully tested from −50 ºC to 200 ºC while demonstrating an output voltage variation of less than 25 mV under the full range of input voltage. Line regulation tests from 10 V to 35 V show a 3.7-ppm/V supply sensitivity. With the use of a high-temperature ceramic output capacitor, a 5-nsec edge, 0 to 220 mA, 1-µsec pulse width load current induced only a 55 mV drop in regulator output voltage. In the targeted application, load current pulse widths will be much shorter, thereby improving the load transient performance. Full temperature and input voltage range tests reveal the no-load supply current draw is within 330 µA while still providing an excess of 200 mA of load current upon demand.

Drug resistant bacteria pathogen poses a severe threat to human health. Bacterial drug efflux pumps are transporter proteins involved in the export of antibiotics out of cells. Efflux by transporters is one of the major drug resistant mechanisms. Multidrug efflux pumps can transport multiple classes of antibiotics and are associated with bacteria multiple drug resistance (MDR). Overproduction of these pumps reduces susceptibility of bacteria to a variety of antibiotics. MDR regulators are cytoplasmic proteins that control the expression level of MDR transporters in response to the cellular concentration of antibiotics. This thesis research focuses on three main directions in the area of bacteria drug resistance: the structural and functional study of a MDR transporter, the characterization of a novel MDR regulator protein, and the development of a sensing method for the detection of glycopeptide antibiotics. Acriflavine resistance protein B (AcrB) in Escherichia coli belongs to resistance nodulation division (RND) superfamily of efflux transporters. It plays an important role in confering multidrug resistance in Gram-negative bacteria. The functional unit of AcrB is a trimer in vivo. However, the relationship between AcrB trimer stability and functionality remains elusive. In chapter 2, a residue that is critical for AcrB trimerization, Pro 223, was identified. The replacement of Pro 223 by other residues destabilized AcrB trimer, and thus decreased its activity. The loss of transport activity could be partially recovered when the AcrB trimer was stabilized by the introduction of a pair of inter-subunit disulfide bond. In chapter 3, a systematically alanine-scanning study of the producing loop (amino acid residues 211-240) was conducted. Five residues in the loop were found to be important for AcrB activity. These residues form a collar or belt in the loop close to the tip. These mutation studies revealed new insight into the conformation of the loop during AcrB trimerization. In chapter 4, residue Arg 780 was identified to be crucial for the pump function of AcrB. The study results indicated that Pro 223 serves as a “wedge” and Arg 780 as a “lock” via hydrogen bonding between the backbone carbonyl oxygen of Pro 223 and side chain of Arg780. Similar as Pro 223, replacement of Arg 780 by other residues drastically decreased the activity of AcrB. Dissociation of the AcrB trimer also contributed to the decrease of activity. However, the introduction of inter-subunit disulfide bond could not restore the function of the mutant, indicating that Arg 780 plays multiples roles in the operation of AcrB. In chapter 5, a MDR regulator ST1710 from the archaeon Sulfolobus tokodaii, homologous to the multiple-antibiotic resistance repressor (MarR) family bacterial regulators, was characterized in vitro. The binding affinities of ligands and double strand (ds) DNA for ST1710 were measured. The presence of substrates suppressed the interaction between ST1710 and dsDNA, which indicated that ST1710 functioned as a repressor in vivo. Finally, in chapter 6, a direct fluorescence polarization based method for the detection of glycopeptide antibiotics is developed. Briefly, the acetylated tripeptide L-Lys-D-Ala-D-Ala was labeled with a fluorophore (fluorescein isothiocyanate or AlexaFluor 680) to create a peptide probe. The fluorescence polarization signal of the peptide probe increased upon binding with glycopeptide antibiotics in a concentration dependent manner. The detection is highly selective toward glycopeptide antibiotics. The designed method is expected it to have broad applications in both research and clinical settings.

Snap bean (Phaseolus vulgaris L.) production by large scale commercial producers in Ethiopia is under intensive production and relies on high rates of nitrogen (N) fertilizer and irrigation during the dry season. Despite increasing interest to produce this crop, small scale farmers cannot afford the high cost of N fertilizer. Field and greenhouse experiments were conducted to test snap bean production under a low input production system better suited to small scale resource limited farmers. Field experiments were conducted in 2011 and 2012 under rain fed conditions, and in 2012 under irrigation, at three locations (Debre Zeit, Hawassa, Ziway) representing different climate zones in Ethiopia. This experiment used three N treatments: 0 and 100 kg N ha-1, and inoculation with Rhizobium etli [HB 429], and eight cultivars: Andante, Boston Contender Blue, Lomami, Melkassa 1, Melkassa 3, Paulista and Volta. The general objective of the field experiment was to determine the potential of snap bean production under a low input production system using rhizobium inoculation as the nitrogen source, and use rain fed conditions. Results obtained indicated that rhizobial inoculation and applied inorganic N increased on average the marketable pod yield of snap bean under rain fed conditions by 18 % and 43%, respectively. Nodulation and subsequent N2 fixation was not effective in improving yield or other traits of snap bean pod under irrigation, although applied N increased marketable yield by 33%. Melkassa 1 was the most suitable cultivar for a reduced input production system due to its successful nodulation characteristics, greatest N2 fixation levels and consistently good performance across locations under rain fed conditions. Commercial cultivars possessed the best pod quality characteristics and they yielded better under irrigation. Cultivars interacted with locations to affect pod traits including total soluble solids and concentrations of protein, calcium, and potassium under rain fed conditions. Snap bean cultivrs produced at Debre Zeit and Hawassa were similar in marketable yield and several other traits particularly under rain fed conditions. Zinc (Zn) concentration in pods was greatest at Hawassa both under rain fed and irrigated conditions. Conditions at Debre Zeit were the most conducive for supporting biological N2 fixation for snap bean production. The eight cultivars were also used for a greenhouse study that was evaluated treatments of drought stress of 50% field capacity (50% FC) during the vegetative (V4.4), flowering (R6) and pod formation (R7) developmental stages. Our result showed that drought stresses during reproductive stages (R6 and R7) were the most sensitive stages in deteriorating the quality of snap bean pods. Drought stress increased protein, phosphorus and Zn concentrations but it reduced iron concentration in snap bean pods. All cultivars had a similar response to drought stress. A second greenhouse experiment was conducted to test foliar application of growth regulators: the control, 10-5 M and 10-4 M concentrations of each of abscisic acid (ABA), kinetin and salicylic acid (SA); and two concentrations of yeast extract (4 g l-1 and 8 g l-1), under drought (50% FC) stressed and unstressed conditions. Foliar application of SA on snap bean under greenhouse conditions reduced the impact of drought stress, particularly the pod quality parameters: marketable yield, pod curving, texture and appearance of snap bean pods. However, application of ABA, kinetin and SA reduced pod quality of snap bean under unstressed conditions. In conclusion, pod yield improvement could be achieved by a N2 fixation system under rain fed conditions, which is more sustainable than N fertilizer inputs. Pod quality was also adequate for commercial export production. Rhizobium inoculant can therefore be used as an alternative N source, particularly under low input production system for resource-limited small-scale snap bean producers.

Abstract S. aureus has 16 predicted two-component systems (TCS) that respond to a range of environmental stimuli, and allow for adaptation to stresses. Of these 16, three have no known function, and are not homologous to any other TCS found in closely related organisms. NsaRS is one such element, and belongs to the intramembrane-sensing histidine kinase (IM-HK) family, which is conserved within the Firmicutes. The regulators are defined by a small sensing domain within their histidine kinase, suggesting that they do not sense external signals, but stress in or at the membrane. Our characterization of NsaRS in this work reveals that, as with other IM-HK TCS, it responds to cell-envelope damaging antibiotics, including phosphomycin, ampicillin, nisin, gramicidin, CCCP and penicillin G. Additionally; we reveal that NsaRS regulates a downstream transporter, NsaAB, during nisin-induced stress. Phenotypically, nsaS mutants display a 200-fold decreased ability to develop resistance to another cell-wall targeting antibiotic, bacitracin. Microarray analysis reveals the transcription of 245 genes is altered in a nsaS mutant, with the vast majority down-regulated. Included within this list are genes involved in transport, drug-resistance, cell-envelope synthesis, transcriptional regulation, amino acid metabolism and virulence. Using ICP-MS, a decrease in intracellular divalent metal ions was observed in an nsaS mutant, when grown under low abundance conditions. Characterization of cells using electron microscopy reveals that nsaS mutants also have alterations in cell-envelope structure. Finally, a variety of virulence related phenotypes are impaired in nsaS mutants, including biofilm formation, resistance to killing by human macrophages and survival in whole human blood. Thus NsaRS is important in sensing cell wall damage in S. aureus, and functions to reprogram gene expression to modify cell-envelope architecture, facilitating adaptation and survival. Interestingly, in our microarray analysis, we observed a more than 30-fold decrease in transcription of an ABC transporter, SACOL2525/2526, in the nsaS mutant. This transporter bears strong homology to nsaAB, and is currently uncharacterized. Exploration of the role of SACOL2525/2526 revealed that, along with NsaRS, it too responds to cell-envelope damaging antibiotics. Specifically, its expression was induced by phosphomycin, daptomycin, penicillin G, ampicillin, oxacillin, D-cycloserine and CCCP. Mutation of this transporter results in increased sensitivity to the antibacterial agent daptomycin, and decreased sensitivity to free fatty acids. These findings are perhaps explained by altered membrane fluidity in the mutant strain, as the transporter null-strain is more readily killed in the presence of organic solvents, such as toluene. In addition, SACOL2525/2526 mutants have a decreased ability to form spontaneous mutants in response to several other peptidoglycan synthesis targeting antibiotics, suggesting a role for SACOL2525/2526 in antibiotic resistance. Inactivation of this transporter alters the cell envelope, and produces similar effects to those observed with the nsaS mutant, with increased capsule production, that may provide resistance to lysostaphin. Interestingly, the nsaS microarray revealed that this TCS negatively regulates only 34 genes, including 6 out of the 10 major secreted proteases. Despite a number of reports in the literature describing these enzymes as virulence factors, the data is often conflicting. Therefore, the contribution of proteases to CA-MRSA pathogenesis was investigated, by constructing a strain lacking all 10 extracellular protease genes. Analysis of this strain using murine models of infection reveals secreted proteases significantly impact virulence in both localized and systemic infections. Additionally, inactivation of these enzymes strongly influences survival in whole human blood, and increases sensitivity to antimicrobial peptides. Using a proteomics approach, we demonstrate that the contribution of secreted proteases to pathogenicity is related to differential processing of a large number of surface-associated virulence factors and secreted toxins. Collectively these findings provide a unique insight into the role of secreted proteases in CA-MRSA infections.

Previously our laboratory had identified a novel component of the Staphylococcus aureus regulatory network, an extracytoplasmic function ó factor, óS, involved in stress response and disease causation. Here we present additional characterization of óS, demonstrating a role for it in protection against DNA damage, cell wall disruption and interaction with components of the innate immune system. Promoter mapping reveals the existence of four unique sigS start sites, one of which appears to be subject to auto-regulation. Transcriptional profiling revealed that sigS expression remains low in a number of S. aureus wild-types, but is upregulated in the highly mutated strain RN4220. Further analysis demonstrates sigS expression is inducible upon exposure to a variety of chemical stressors that elicit DNA damage, including methyl methanesulfonate (MMS) and ciprofloxacin, as well as those that disrupt cell wall stability, such as ampicillin and oxacillin. Ex vivo transcriptional analysis reveals that significant expression of sigS can be induced upon phagocytosis by RAW 264.7 murine macrophage-like cells. Regulation of óS appears to be unique, as the downstream encoded protein, SACOL1828, seemingly acts as a positive activator, rather than as an expected anti-sigma factor. Using a global transposon screen we have elucidated additional genes implicated in the regulation of sigS, including those involved in cell wall stability, cellular detoxification, virulence and DNA base excision repair. Phenotypically, óS mutants display sensitivity to a broad range of DNA damaging agents, such as ultraviolet light, MMS and ethidium bromide. These effects are seemingly mediated via regulation of the purine biosynthesis pathway, as microarray, proteomic and qRT-PCR analysis of óS mutants reveal decreased transcription of all genes involved. Enzymatic profiling of PurA involved in adenine biosynthesis, demonstrates decreased activity in the óS mutant. Finally, we provide further evidence for the role of óS in S. aureus pathogenesis, revealing that sigS mutants display decreased ability to cause localized infections and are impaired in their interactions with components of the human innate immune system. Collectively, our data argues for the important, and perhaps novel, role of óS in the stress and virulence responses of S. aureus.

M. Tech. Business Administration / The purpose of the study was to establish the relationship between job satisfaction and productivity at the National Regulator for Compulsory Specifications (NRCS), given the fact that the organisation has been characterised by various people issues since inception, and suffered three employee strikes during a period of five year. Many challenges, ranging from disruptions emanating from labour disputes, and financial challenges which adversely affected the organisation's overall performance, were experienced. Given the critical role that job satisfaction and productivity play in determining the efficiency, effectiveness and sustainability of organisations, it was paramount to understand what motivates them and to what extent they are satisfied by the organisations and other contextual variables.

Denna högskoleavhandling beskriver konstruktionen av ett system vars funktion är att PID-reglera ett linjärställdon kopplad till venturi. Syftet har varit att få fram en reglering på venturin så att förutsättningarna förblir desamma vid mätning av olika temperaturer och lufttryck i en testrigg. Denna testrigg används för att utveckla produkten Varivent som används för att uppfylla högre miljökrav på förbränningsmotorer. I arbetet beskriver jag de olika krav som funnits för att bygga det nya systemet, dessa var ingångar, utgångar, mikroprocessor, reglering, kommunikation samt övriga krav. Jag diskuterar de svårigheter och möjligheter som är förknippade med kraven och tar även upp de komponenter jag använt samt deras egenskaper. Det svåraste momentet har varit PID-regulatorn som både varit en viktig och en svårlöslig del i konstruktionen av systemet. Slutligen diskuterar jag resultatet där jag, i en analys, kan se att jag kunde underlättat för mig själv med andra angreppsvinklar men att det slutliga resultatet ändå blivit mycket tillfredsställande. / This bachelor thesis describes the design of a unit the function of which is to regulate, using PID controls, a linear mechanical adjusting screw coupled to a variable venturi flow system. The design criteria has been to create, in a test rig, a venturi control system that gives an output that is not affected by changes in either air temperature or pressure. The test rig is used for the development of Varivent, a product used to reduce the environmental impact of the internal combustion engine. In my thesis work I describe the various and necessary elements of the project. These can be termed inputs, outputs, microprocessors, regulators and communicators. I discuss the difficulties and possibilities associated with the design criteria and mention the components used and their different attributes. The most challenging part of the project has been the design of the PID regulator, which, whilst being the heart of the system, has also been the most difficult part of the system to design. Finally I discuss my results where, in an analysis, I see that I could have made things easier for myself had I approached the problems in other ways but that the final result was, despite this, very satisfactory.