Performing condition monitoring related tasks on any machinery is an essential element of their rational maintenance. Endeavours to detect an incipient fault within a system serve multiple purposes from increasing the safety of people responsible for operating the machines through decreasing the running and operational costs, allowing time to plan for the inevitable repairs and making sure that the downtime of the machine is kept to an absolute minimum. All these tasks gain extra importance in a case when machines are operated in dangerous conditions putting people's lives in potential jeopardy - for instance in the field of operating a helicopter. The robust assessment of the condition of gearboxes used by helicopters has recently been given an increased attention due to a number of accidents which followed an undetected drive train component failure. The majority of the on-board mounted condition monitoring systems use vibration response signals which are specifically processed to obtain a single number which is representative of a condition of a given monitored drive train component. Those signal processing methods are called Condition Indicators (CIs). There are a number of such CIs which are already in use and they seem to adequately indicate faults in most of the cases. However in a number of instances it has been observed that the most popular parameters like Crest Factor or FM4 failed to dependably reflect the true condition of the gear causing serious accidents, some of which resulted in a number of lives being lost. For this reason the presented research is focused on investigating the limitations of the existing CIs and designing a set of improved CIs. The development process is based on overcoming the drawbacks of thetechniques used in existing CIs combined with the intelligence gathered while analysing the acceleration vibration signals which contained a gear or a bearing fault. Five new CIs are proposed and the details of their design are documented. Both the existing and the proposed CIs are applied on the available, uncorrelated datasets. The results of the comparison show that the newly developed CIs are capable of indicating a gear or a bearing fault in a more robust and dependable fashion. Each proposed CI alone may not be the most robust indicator of the actual condition of the monitored component hence the output from all proposed CIs is combined into a single indication through use of a novel data fusion model. The Combined CI created based on the data fusion model is observed to be more robust compared to each CI alone, hence it may increase the confidence level of the decision making routine and is expected to decrease the number of false alarms. The methods of the existing CIs, the proposed CIs and the data fusion techniques as well as the results of the comparison between the different approaches are present in this thesis.

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The condition of water and wastewater pipelines has been deteriorating with time and since this infrastructure is out-of-sight, the assessment has been neglected over the years. The advancement of technology in various fields has provided pathway for development of several technologies for assessment of the condition of pipeline systems. However, there is no standard guidance or tool for the utilities to use these technologies appropriately. The utilities are unaware of the present state-of- the- art technologies. The predictability and condition assessability indices will help utilities predict a probable failure and take steps to prevent it. The predictability index will indicate the inherent, theoretical predictability of key types of pipe failures. The pipe failure predictability index would be a score calculated by identifying high priority pipe types, characterizing their failure modes, mechanism, conditions, and indicators, reliability of indicators, lead-time of the indicators, and other factors. The condition assessability index will indicate the technical and economical methods of preventing key types of pipe failures. The pipe failure condition assessability index is similar to the predictability index, but it takes into account the capability of existing inspection technologies for measuring the required failure indicator parameters. Prestressed Concrete Cylinder Pipes are used in large diameter water pipelines throughout the United States to convey large volumes of water. Prestressed Concrete Cylinder Pipes are complex composite pipes. Therefore, prediction and prevention of failure of these pipelines is complex and requires a better understanding of the system. This research concentrates around development of Predictability and Condition Assessability Indices for PCCP pipelines. / Master of Science

Les bienfaits d’une pratique régulière de l’activité physique sur la composition corporelle et ses complications métaboliques sont bien établis dans la littérature. Cependant, les interventions cliniques prônant une perte de poids par la pratique d’activité physique seule ne procureraient pas les bénéfices recherchés sur la composition corporelle et la santé métabolique contrairement à une intervention de saines habitudes alimentaires prescrite à elle seule. Cela soulève la question à savoir dans quelle mesure le stimulus de l’exercice a été suffisamment caractérisé pour refléter l’empreinte à long terme d’un mode de vie actif sur le risque de développer l’obésité et les complications métaboliques associées. Ce mémoire documente ce problème en résumant les évidences et en présentant des données montrant qu’une classification basée sur la capacité aérobie et la pratique d’activité physique permettent de mieux refléter l’impact d’une pratique d’activité physique vigoureuse tout au long de la vie sur la composition corporelle et la santé métabolique. En outre, nous renforçons la pertinence de cette classification en présentant des données provenant de l’Étude des familles de Québec (QFS) comparant les individus « fit-actifs » à ceux « unfit-inactifs ». Les résultats des deux sexes montrent que les individus « fitactifs » présentent des profils morphologique et métabolique beaucoup plus favorables que ceux des individus « unfit-inactifs ». Les bénéfices semblent provenir davantage des variations de condition cardiorespiratoire que celles de la pratique d’activité physique. En résumé, ces observations suggèrent que les bénéfices d’une pratique d’activité physique vigoureuse à long terme seraient bien représentés par une classification basée sur la capacité aérobie et la pratique d’activité physique rapportée. / Regular physical activity participation has been recognized over time as an essential component of a lifestyle contributing to the prevention of obesity and non-communicable diseases. Recently, the emphasis on sedentary behaviors and physical inactivity as additional factors, independent of physical activity practice, has to some extent confirmed the relevance to encourage regular physical activity habits in the prevention and management of obesity. This optimistic vision is however toned down by some clinical interventions that demonstrate that the inclusion of a physical activity component in a weight reducing program is not producing substantial additional benefits on body composition and metabolic health compared to when a healthy diet is prescribed alone. This raises the question as to which extent the exercise stimulus has been adequately characterized to reflect the long-term print of an active lifestyle on the risk to develop obesity and related metabolic complications. This thesis documents this issue by summarizing evidences and presenting relevant data showing that a classification based on aerobic fitness and physical activity practice provides indications of greater impact of a lifelong vigorous physical activity practice compared to what may be anticipated from existing literature. Furthermore, we reinforce the pertinence of this classification by presenting relevant data from the Quebec Family Study to compare the fit-active to the unfit-inactive individuals. For both sexes, fit-active individuals displayed much more favorable morphological and metabolic profiles than their unfit-inactive counterparts. The fitness variations of the profile seem to generate more benefits than the physical activity practice in the profile. In summary, these observations suggest that the benefits of a lifelong physical activity practice may well be reflected by a classification based on both fitness and reported physical activity practice.

Condition based monitoring is widely used for the determination of the health of machines. The Nottingham Trent University Computing Department has developed a new system, the Incremental Motion Encoder (!ME), which is based on the time interpolation of the digital signals produced by an optical encoder. Experiments have shown that the !ME can be used as a condition based maintenance sensor as it is possible to detect rolling element defects, an unbalanced shaft and oil contamination of a bearing. The system uses a geometrically configured optical device to scan a precision encoder disc and Digital Signal Processing technology is used to interpret the signals. Previous work has demonstrated the qualitative usefulness of the 1ME. However, further work was needed to assess the accuracy of the measurements, to analyse the principles of the 1ME, to validate the performance of the existing device and to develop methods for error definition and error compensation. Testing and experimentation on the existing experimental system have been carried out by the Candidate and an understanding gained of the device. The sources of error of the 1ME have been identified, which had not been quantified previously. Measuring and compensating for the three main sources of error, read head position, eccentricity of the encoder disc and encoder abnormalities are the three major tasks of the project. Modifications to the experimental rig have been developed in order to allow these tasks to be addressed. The Candidate has developed three different types of techniques to measure the position error of the read heads. A pattern recognition method was developed and is successful for 1ME systems that use an encoder disc with significant grating line errors. A second method using Fast Fourier Transform (FFT) has been developed to exploit the fact that the difference in the phase angles, obtained using a FFT, gives the angle between the read head positions. The new experimental system is now able to obtain the angular position of the read heads by using the index grating line. The third method relies on the presence of the index grating line on the encoder disc which may not be present in all systems. Eccentricity of disc centre relative to the centre of rotation affects the correct calculation of the angular position of the encoder disc. Algorithms have been developed by the Candidate in order to compensate for this type of error. Experimental results have shown that angular position error can be corrected successfully. The Candidate has developed methods for detection of small abnormalities of the encoder disc by using a multiple averaging technique. Computational algorithms have been developed to correct the encoder disc abnormalities by using individual information from each read head, promising results have been obtained from the experimental 1ME. An 1ME device can be tailored to fulfil the desired requirements of resolution, bandwidth and accuracy. A self calibration instrument can be developed by using the previously mentioned techniques in order to self calibrate and increase the accuracy and reliability of an IME's results.

Condition monitoring business has been of interest to Sulzer since the 1990s when the Sulzer Diagnostic System (SUDIS) was developed. However, since the invention of SUDIS, Sulzer has had limited commercial success with condition monitoring products and services. Several recent investigations at Sulzer have explored possibilities for new machine monitoring business, with the most recent being the condition monitoring equipment survey of Nyitray. This report leads on from the work of Nyitray to evaluate the attractiveness of current machine monitoring markets and the strength of current and concept control and monitoring business models. Sales and customer support services (CSS) staff in all business segments and areas were surveyed for information regarding customer demand for machine monitoring solutions. The results of the survey lacked a unified view on customer needs, indicating that customer needs vary significantly with industry and region. Results also indicated that Sulzer sales and CSS staff currently have very little contact with customers regarding machine monitoring issues, which was expected since Sulzer currently has very limited machine monitoring offers. Overall customer interest in machine monitoring for cost saving purposes is high. Moreover, some customers expect equipment manufactures like Sulzer to support their equipment with machine monitoring offers. Business model environmental factors for each Sulzer Pumps focus market were identified allowing the most attractive markets for machine monitoring business to be selected. A survey of Sulzer Pumps business segment heads also contributed to the market selection process. This evaluation concluded that the water and power generation industries had favourable markets for machine monitoring business, mainly because Sulzer has a good competitive position in these markets. Unfortunately pumps in the electricity generation industry are relatively reliable compared to other machinery such as electrical generators. Hence, opportunities identified in the electricity generation industry seemed to be more appropriate for Sulzer Turbo Services than Sulzer Pumps. However, cross-divisional collaboration of Sulzer Pumps and Sulzer Turbo services would allow Sulzer to offer solutions for entire drivetrains. Other opportunities suitable for Sulzer Pumps were identified in the district heating and water industries, with energy monitoring being a common theme. An evaluation of the oil pipeline industry yielded that there is significant market demand for machine and pipeline monitoring. However, Sulzer currently does not have the experience or resources to provide the demanded monitoring services independently. Hence searching for key partners or acquisition targets was acknowledged as an essential activity for Sulzer Pumps to enter this market. Another means of market entry would be to develop novel technology or integrate emerging technologies (e.g. online viscosity sensors) into new pipeline monitoring solutions, i.e. to create a novel value proposition. Subsequent feedback from Sulzer alliance managers concluded that oil pipeline customer acquisition may be difficult since many pipeline companies already have monitoring solutions which they are satisfied with. Hence the oil pipeline market is not recommended for new machine monitoring business ventures. ABS pump control and monitoring solutions are currently the only machine monitoring solutions offered by Sulzer Pumps. In this study the business model behind these solutions was analysed to evaluate its strength and identify areas for improvement. Although the ABS control and monitoring business model is profitable, sales figures are below their potential. Recommendations to improve the business models effectiveness mainly focused on improving channels through which Sulzer connects with its customers. These included improving Sulzer digital marketing material, improving product selection tools, increasing complementary advertising and quotation contents to connect Sulzer control and monitoring products with pump equipment products, and most importantly increasing the amount of sales and CSS staff training.

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No description available.

The western king prawn (Penueus Zarisulcutus) is one of the most economically valuable species of crustacean in Australia. The experiment was carried out for 60 days to determine the growth, survival, haemolymph osmolality and organosomatic indices of the western lung prawn (2.95 f 0.26 g mean initial weight) reared at 10, 22, 34 and 46 g L of salinities. In addition, haemolymph osmolality and osmoregulatory capacity (OC) of the western king prawn (5.37 f 0.1 g mean initial weight) reared at salinities (10, 22, 34 and 46 g/L) were determined following 7, 14 and 21 minutes of air exposure and compared with the brown tiger prawn (P, esculentus). Mean final weight, total length, carapace length and specific growth rate (SGR) of the western king prawn were highest at a salinity of 34 g/L. Moult increments (in weight and total length) of the western king prawn were not significantly different (P > 0.05) when reared at four different salinities. Food conversion ratios were lowest in prawns reared at salinities of 22 and 34 g/L. Survival of the western king prawn was highest at a salinity of 22 g/L and lowest at a salinity of 10 g/L. Haemolymph osmolality of the western king prawn increased with an increase in salinity and weight. Isosmotic points of the western king prawn calculated from regression lines between haemolymph and medium osmolality were 28.87, 29.46 and 31.73 g / L at 0, 20 and 60 days of rearing (accordingly to 2.95 f 0.26; 4.02 f 0.47; 5.79 f 0.64 g body weight), respectively. Tail moisture content of the western king prawn decreased with the increase of salinity. After 60 days of rearing, the lowest hepatopancreas moisture content of the prawns was at a salinity of 22 gL. Wet weight and dry weight hepatosomatic indices of the prawns were highest when reared at a salinity of 22 gL. / Wet weight and dry weight tail muscle indices of the prawns were highest at a salinity of 34 gL. Isosmotic points of the western king prawn were 33.79; 33.29; 32.75 and 33.10 g/L at 0, 7, 14, and 21 minutes of air exposure, respectively. Isosmotic points of the brown tiger prawn were 30.89; 31.89; 32.09 and 31.07 g/L at 0, 7, 14, and 21 minutes of air exposure, respectively. Air exposure reduced OC of both the western king prawn and brown tiger prawn. OC of both species at a salinity of 10 giL was reduced significantly after 14 minutes of air exposure. Twenty-one minutes of air exposure did not change OC of the western king prawn reared at salinities of 22, 34 and 46 g/L. OC of brown tiger prawn reared at 22 g/L decreased after 21 minutes of air exposure while OC of the brown tiger prawn reared at 46 g/L decreased after 7 minutes of air exposure. The results indicate that both species spent less energy on osmoregulation at 34 gL salinity than at other salinities. The results suggest that the optimum salinity for rearing of western king prawns ranges from 22 g/L to 34 g/L. Salinities of 10 and 46 gL are unsuitable for rearing brown tiger prawns and salinity 10 g/L is unsuitable for rearing western king prawns. Furthermore, a salinity range from 30 g/L to 32 gL is suitable for the culture of brown tiger prawns.

Let X be an affine algebraic variety with a transitive action of the algebraic automorphism group. Suppose that X is equipped with several fixed point free non-degenerate SL_2-actions satisfying some mild additional assumption. Then we prove that the Lie algebra generated by completely integrable algebraic vector fields on X coincides with the set of all algebraic vector fields. In particular, we show that apart from a few exceptions this fact is true for any homogeneous space of form G/R where G is a linear algebraic group and R is a proper reductive subgroup of G.