Remote data acquisition for condition monitoring of wind turbines

While the number of offshore wind turbines is growing and turbines getting bigger and more expensive, the need for good condition monitoring systems is rising. From the research it is clear that failures of the gearbox, and in particular the gearwheels and bearings of the gearbox, have been responsible for the most downtime of a wind turbine. Gearwheels and bearings are being simulated in a multi-sensor environment to observe the wear on the surface

Feeding Strategies Based on Probing Control for E. coli and V. cholerae Cultivations

The recombinant DNA techniques have made it possible to produce many different proteins for a wide range of applications. The vector encoding for the recombinant protein is often inserted in the bacterium E. coli as it is a well studied and a well-known organism. To achieve a high productivity, it is important to reach a high cell density. This is obtained through fed-batch operation where the nutrient, usually glucose, is added continuously. The feeding strategy should be designed to avoid starvation and overfeeding. This is not an easy task as on-line measurements of key variables are normally not available. A probing feeding strategy using the measurements of the standard dissolved oxygen sensor is developed by M. Åkesson. The key idea is to superimpose pulses on the feed-rate and make use of the responses in the dissolved oxygen in a feedback algorithm. Also, when the maximum transfer capacity of the reactor is reached the feed-rate is decreased in order to keep the reactor working under aerobic conditions. The strategy has been successfully implemented in cultivations with different E. coli strains and on different scales. The probing feeding strategy is further developed in many aspects in this thesis. Firstly, it is implemented with good results also in V. cholerae cultivations, which shows how general the strategy is. Also, a model of a bio-reactor operating in fed-batch mode is presented and verified. The effect on the tuning rules of the probing controller is investigated. The probing feeding strategy is further improved for a more efficient product synthesis. This new fermentation technique manipulates the temperature when the maximum oxygen transfer capacity of the reactor is reached. The strategy consists of a mid-ranging controller structure and a modified probing controller. It is analysed and evaluated in experiments and simulations. Furthermore, some E. coli production strains need additions of amino acids or complex media besides the carbon nutrient to grow and produce the recombinant protein. The probing control concept is therefore extended in order to handle these situations. Feeding strategies for dual feeding of amino acids or complex media and glucose are developed

Standardized exercise tests in horses : current situation and future perspectives

The purpose of this literature review is to clarify how exercise capacity can be measured in horses and which standardized exercise tests (SETs) exist. In this review, the measurement of the exercise capacity of horses is discussed and the standardized exercise tests (SET) are described. Two main types of SETs are used. Laboratory or treadmill tests are easy to standardize and provide more options to use all kinds of measuring devices, since the horse stays on the treadmill. On the other hand, field tests are conducted under the natural conditions associated with the specific sports discipline, and are easier to implement in the training schedule. However, field tests encompass interfering variables, such as weather conditions, ground surface conditions and the rider or jockey. Several variables are measured in order to calculate the fitness level which may be expressed by different parameters, such as V200 (speed at a heart rate of 200 beats per minute), V1a4 (speed at a blood lactic acid level of 4 mmol/L) and VO2max (maximum oxygen uptake)

The Structure and C=C Vibrational Frequencies of the all- trans Polyenes C2nH2n+2(n=2-15), C2nH2n(Me)2(n=2-13), and C2nH2n(tert-Butyl)2(n=2-5): Computational Results

Carbon-carbon bond lengths and C=C vibrational frequencies are reported for the linear, all-trans unsubstituted C2nH2n+2 (n=2-15), methyl capped C2nH2nMe2 (n=2-13), and tert-butyl capped C2nH2n(tert-butyl)2 (n=2-5) polyenes (C2h) calculated at the B3LYP/6-311++G(d,p) level. The C=C/C-C bond length alternation remains evident at this level for the unsubstituted and methyl capped polyenes as the chain length increases; the center-most difference in the length of the C-C/C=C bonds is ~0.06 Å for C30H32 and C26H26Me2. The Ag, in-phase, harmonic C=C Raman frequency for the unsubstituted polyenes decreases from 1699.2 cm-1 (n = 2) to 1528.9 cm-1 (n=15); the anharmonic frequency decreases from 1651.5 cm-1 (n = 2) to 1547.7 cm-1 (n = 8). The harmonic C=C frequency for the methyl capped polyenes decreases from 1717.9 cm-1 (n = 2) to 1539.6 cm- 1 (n= 13), and the anharmonic C=C frequency decreases from 1675.0 cm-1 (n = 2) to 1562.8 cm-1 (n = 7)

Parameter Estimation of a Model Describing the Oxygen Dynamics in a fed-batch E. coli Cultivation

A model describing the oxygen dynamics in an E. coli fed-batch cultivation is presented. In a linearised version the parameters are estimated and validated with good results. The model is used to discuss the guidelines for feed controller tuning derived in Åkesson 2001

A modified probing feeding strategy: control aspects

The paper presents a fermentation technique, which combines the advantages of the probing feeding strategy and the temperature limited fed-batch technique. The early phase of the cultivation is run under glucose limited conditions by using the original probing technique. When the maximum oxygen transfer capacity of the reactor is reached, the temperature is decreased to lower the oxygen demand. A slight glucose excess, achieved by downwards probing pulses, guarantees that thetemperature is the only limiting factor. To achieve a good control of the dissolved oxygena mid-ranging controller manipulating the stirrer speed and the temperature is used. A model describing the temperature influence on the cellmetabolism is derived to facilitate the controller design. The feeding strategy is illustrated by an experiment

Kvalifikationskrav på arkivarier : en undersökning av svenska myndighetsarkiv

The aim of this master’s thesis is to examine which competencies and qualifications Swedish government agencies require when hiring records managers today. Recently, the archival sector has encountered several challenges regarding technical solutions for electronic archiving. This thesis also attempts to address whether these changes affect the need for specific qualifications in records managers. Records managers and those responsible for the recruitment at seven government agencies in southern Sweden have been interviewed about what skills they consider important for records managers. Additionally, required skills in ten job advertisements from these government agencies have been analysed. Only government agencies have been analysed, as it is mandatory for them to transcend to an operationally based file classification system, a method that seems to play an important part in Swedish records management when an increasing number of archives go digital. The theoretical framework is based on Per-Erik Ellström’s taxonomy of qualifications, and his analysis of how these are affected when organisations decide to increase their computerised areas. The results show that all qualifications in Ellström’s taxonomy are required when employing records managers today, except psycho-motorical skills and some of the skills known as tacit knowledge. Also, none of the informants thought that the need of any qualifications should be replaced when archives go digital, but rather that records managers need to know more today than previously. He or she needs to be able to work both in the traditional paper-based archive, as well as in the e-archive. The records manager also needs knowledge in both the previously used file classification system (allmänna arkivschemat), and the new operationally based file classification system. It appears that the introduction of the operationally based file classification system has affected the qualification requirements to a certain degree, but the informants have different opinions and experiences regarding this question. Most of them agree that the increased amount of digital material and the challenges concerning e-archives, combined with the operationally based file classification system, affect which qualifications and knowledge records managers need today

The Wellesley News (04-20-1933)

https://repository.wellesley.edu/news/1945/thumbnail.jp