Detection of NPT and Drilling Events on the NCS from Depth-based Drilling Mechanics

Drilling events are subsurface related events that result in non-productive time (NPT) and increased costs. The aim of this thesis was to improve the understanding of drilling events to help mitigate non-productive time in drilling operations. NPT and drilling events related to drilling operations was studied and a consistent data analytics workflow in MATLAB was developed. An initial case study was conducted, and a prototype MATLAB workflow developed, testing different approaches for drilling events detection. Based on the result from the initial case study from the Northern North Sea, the workflow was updated and 20 wells from the North Sea and Norwegian Sea were analysed. Mechanical specific energy and drilling strength models were calculated from depth-based drilling mechanics, and combined with the ratio between the two, the MSE/DS ratio, a workflow was created to detect drilling events. Based on cut-off values from the initial case study, the developed workflow enabled the detection of bit balling, vibrations, and bit wear. Unconfined compressive strength (UCS) was estimated from Sonic data and lithology, enabling the detection of hard rock. Two methods were developed to estimate lost drilling time due to drilling events: The WOB-method and the Torque-method. Utilizing the linear relationship between ROP-WOB and Torque-WOB for efficient drilling, efficient bit-lines were created, enabling the estimation of lost drilling time due to inefficient drilling. By comparing bit changes to detected drilling events, lost time due to unplanned tripping was estimated. The result from the initial case study showed a strong match between the reported events and the developed workflow. Among the 20 analysed wells, vibrations were the most common detected drilling event, with an average 41 m/km detected pr well. The largest contributor to NPT was bit balling, contributing to 44% of the lost time. On average, 69 hours were lost due to drilling events, equivalent to 5% of the total time for the drilling operations, with an estimated cost of 7 mill NOK. The main advantage of the developed workflow is the ability to discover and map drilling events in offset wells from limited available data in an effectively manner, helping mitigate NPT in future wells.Drilling events are subsurface related events that result in non-productive time (NPT) and increased costs. The aim of this thesis was to improve the understanding of drilling events to help mitigate non-productive time in drilling operations. NPT and drilling events related to drilling operations was studied and a consistent data analytics workflow in MATLAB was developed. An initial case study was conducted, and a prototype MATLAB workflow developed, testing different approaches for drilling events detection. Based on the result from the initial case study from the Northern North Sea, the workflow was updated and 20 wells from the North Sea and Norwegian Sea were analysed. Mechanical specific energy and drilling strength models were calculated from depth-based drilling mechanics, and combined with the ratio between the two, the MSE/DS ratio, a workflow was created to detect drilling events. Based on cut-off values from the initial case study, the developed workflow enabled the detection of bit balling, vibrations, and bit wear. Unconfined compressive strength (UCS) was estimated from Sonic data and lithology, enabling the detection of hard rock. Two methods were developed to estimate lost drilling time due to drilling events: The WOB-method and the Torque-method. Utilizing the linear relationship between ROP-WOB and Torque-WOB for efficient drilling, efficient bit-lines were created, enabling the estimation of lost drilling time due to inefficient drilling. By comparing bit changes to detected drilling events, lost time due to unplanned tripping was estimated. The result from the initial case study showed a strong match between the reported events and the developed workflow. Among the 20 analysed wells, vibrations were the most common detected drilling event, with an average 41 m/km detected pr well. The largest contributor to NPT was bit balling, contributing to 44% of the lost time. On average, 69 hours were lost due to drilling events, equivalent to 5% of the total time for the drilling operations, with an estimated cost of 7 mill NOK. The main advantage of the developed workflow is the ability to discover and map drilling events in offset wells from limited available data in an effectively manner, helping mitigate NPT in future wells

Procrastination and it's Negative Emotional Consequences. How are procrastination related to negative emotional consequences of procrastination and how can it be measured?

Forskning på prokrastinering har flere utfordringer som hindrer oss fra å forklare relasjonen mellom prokrastinering og variabler som prokrastinering har kjente relasjoner med. Denne studien har forsøkt å måle direkte konsekvenser av prokrastinering og videre analysere sammenhengen mellom prokrastinering og dens kjente relasjoner med negative konsekvenser av prokrastinering. På denne måten kan vi observere de problematiske trekkene med prokrastinering på en mer direkte måte. Dette prosjektet målte negative emosjoner knyttet til prokrastinering gjennom selvrapport og fant måleinstrumentet både reliabelt og valid. Studien fant videre at negative emosjoner knyttet til prokrastinering hadde en signifikant relasjon med prokrastinering. Negative emosjoner relatert til prokrastinering predikerte også subjektivt velvære når det var kontrollert for både prokrastinering og nevrotisisme. De direkte implikasjonene fra resultatene er noe begrenset da det kan være mange alternative forklaringer bak funnene. Det ser imidlertid ut til at negative emosjoner relatert til prokrastinering fanger opp problematiske aspekter ved prokrastinering. Dette er noe som de vanlige prokrastineringsskalaene ikke fanger opp, spesielt den mer spesifikke rollen nevrotisisme og mestringstro har i forhold til subjektiv velvære. Vi har også identifisert en sårbar gruppe som det burde forskes mer på. Nøkkelord: Prokrastinering, negative emosjoner, mestringstro, subjektiv velvære, metodologiMuch of the research on procrastination have several challenges that keeps us from explaining the relationships between procrastination and correlated factors. By measuring direct consequences of procrastination and analysing the relations between procrastination and its known relations with negative consequences of procrastination, we can observe the problematic aspects of procrastination more directly. The current research measured negative emotional consequences attributed to procrastination through self-report and found the measure both reliable and valid. The current research also found that negative emotions attributed to procrastination was significantly related to procrastination. It also predicted satisfaction with life even when both procrastination and neuroticism were controlled for. The direct implications we can take from these results are however still limited as there are plausible alternative explanation of these findings. It does however seem that the negative emotions attributed to procrastination captures the problematic aspects with procrastination. This is something the most used procrastination scales do not capture. Specifically, the contributions of neuroticism and self-efficacy. We have also identified a group that suffers from procrastination that should be studied further. More generally, the knowledge on procrastination and its challenging effects should be better informed to students in the educational institutions. Keywords: Procrastination, negative emotions, self-efficacy, subjective well-being, methodolog

The potential of sedimentology and stratigraphy in avalanche-hazard research

Detailed sedimentology studies in cross sections and studies of recent processes on avalanche-dominated colluvial fans have been combined in order to evaluate the characteristic sedimentary facies of avalanche processes. These include rock avalanches, rockfalls, debrisflows and snow avalanches. Moreover, the sedimentary facies provides important data on the mechanics of the depositional processes involved. Avalanche deposits are commonly separated by soil or peat beds, which can be dated by the radiocarbon method. In many cases it is thus in many cases possible to estimate the frequency of different avalanche events through time. Geological data can also be used in combination with other methods to evaluate potential impact or run-out zones. Debrisflow and snowflow events can be recognised in excavations, and the run-out distances for older events can thus be mapped. Snow avalanches commonly transport considerable amounts of debris, and far-reaching snow avalanches can be recognised from the occurrence of scattered clasts in peat or soil successions. Such data can be important in testing statistical and dynamic run-out models. A register of historic and prehistoric rock avalanches is currently being compiled, a database which will be of fundamental importance in the future in evaluating run-out distance for potential bedrock failures. This research as a whole suggests that detailed geological studies involving sedimentology and stratigraphy can be of interest and importance in projects concerned with avalanche hazard

On the relative effect of spawning asynchrony, sperm quantity, and sperm quality on paternity under sperm competition in an external fertilizer

How much of a fitness benefit is obtained by dominant males of external fertilizers from releasing ejaculates in synchrony with female egg-release when engaging in sperm competition, and what is the most important sperm trait for paternity in these situations? The Arctic charr (Salvelinus alpinus) is an external fertilizer experiencing intense male-male competition over reproductive opportunities including sperm competition. To compensate for their disadvantage the sneaker males, which often spawn out of synchrony with the female, produce more and faster sperm than the guarding males. We used controlled in vitro fertilization trials with experimentally produced dominant and subordinate, sneaker males to test what effect relative synchrony in gamete release, sperm quality (i.e., motility and velocity) and sperm quantity have on a male’s fertilization success in pair-wise sperm competitions. When the sneaker males released ejaculates after the guarding male there was no overall difference in fertilization success. The quality (i.e., motility and velocity) of a male’s sperm relative to that of the competing male was the best predictor of male fertilization success regardless of their mating tactic and spawning synchrony. The relative number of sperm cells also had an effect on fertilization success, but mainly when the dominant and sneaker male ejaculated synchronously. Our close imitation of natural sperm competition in charr shows that the sneaker males of external fertilizing species may fully compensate for their disadvantaged mating role by producing ejaculates of higher quality—an adjustment strangely not met by dominants

Rock-avalanche hazard in Møre & Romsdal, western Norway

Flood waves generated by large rock avalanches have caused major disasters in Norway. Many of these events are restricted to a relatively limited zone in the counties Møre & Romsdal and Sogn & Fjordane. Geological studies confirm that this zone has been affected by large-scale rock avalanches throughout the postglacial period. The number of rock-avalanche events is much higher than expected, and many of them are from the latest part of the postglacial period (the last 5000 years), thus in contrast to the general assumption that most of these events occurred shortly after the deglaciation. Rock avalanches and related flood waves often represent a higher risk than other types of avalanches in the region, due to the potential of causing extensive damage. It can be concluded that the avalanche probability limit of 10-3 pr. annum which is used for normal buildings in Norway, is not applicable for rock-avalanche hazard. The study indicates that rock-avalanche hazard should be taken into account in several inhabited areas. More work needs to be done in order to produce hazard-zone maps

On the use of pulsed electric field technology as a pretreatment to reduce the content of potentially toxic elements in dried Saccharina latissima

Seaweeds, like sugar kelp, are increasingly popular for food production, but their application is often limited by the content of iodine and other potentially toxic elements (PTEs). Boiling and blanching are efficient in reducing the iodine content (-38-94%), but are energy demanding processes and could therefore be too expensive for viable commercial applications. Pulsed electric field (PEF) processing is gaining interest for commercial processing of seaweeds, aiming to reduce the energy demand for the pre-treatment. In this work, two conditional settings (energy levels: 2.7 and 14.4 kJ/kg) of PEF were evaluated as pretreatments prior to drying of sugar kelp, and compared to no pretreatment and freezing/thawing at −20/4 °C. Both PEF treatments reduced the iodine content significantly, by approximately 40%, compared to no pretreatment. Similarly, the content of mercury was reduced by approximately 19%. Freezing prior to drying did not significantly alter the content of PTEs in dried kelp. The energy input associated with PEF processing was <10% of the calculated input for traditional processing. These findings are promising as the industry is looking into rapid, non-destructive processing methods for reducing the energy requirements associated with drying and preservation, while improving the safety of products.publishedVersio

Cannibalism and protective behavior of eggs in Arctic charr (Salvelinus alpinus)

From video recordings of spawning events, we quantified protective and cannibalistic behavior of Arctic charr occurring immediately after spawning. The number of fish cannibalizing on stray eggs was examined regarding (a) whether more than one male shed milt during the spawning event, that is, whether sperm competition occurred, (b) whether the sperm competition included few or many males, that is, the intensity of sperm competition, and (c) the density of fish at the spawning site. Response behavior toward egg cannibalism was also examined among females and dominant males in order to determine any parental investment toward protecting the eggs after spawning. Cannibalistic behavior was seen in almost 50% of the spawnings, and the multiple spawning events showed the highest numbers of fish cannibalizing on eggs. Both the number of males releasing milt and the number of fish approaching the spawning site were positively correlated with egg cannibalism. Sperm competition was, however, not a prerequisite for egg cannibalism. Although we also observed partial filial cannibalism, protective behavior of eggs was seen both among dominant males and females, suggesting that charr actually conduct parental care.publishedVersio

Status specific tailoring of sperm behavior in an external fertilizer

Published version. Source at https://doi.org/10.3389/fevo.2016.00135 Why dominant males experiencing intense sperm competition sometimes show low investments in sperm production is not always obvious. One well-documented example is that of the external fertilizing teleost, the Arctic charr (Salvelinus alpinus), where individuals becoming dominant reduce sperm production and sperm swimming speed in water compared to subordinates. Here, we report how ovarian fluid differentially influences sperm velocity of dominant and subordinate male Arctic charr. That is, sperm from dominant males increase their velocity in water diluted ovarian fluid compared to that observed in water, while sperm from subordinates, on the other hand, decrease velocity in ovarian fluid compared to that observed in water. Thus, subordinates, who invest more resources in their sperm and usually show the highest sperm velocity in water, have lower gains from their investment than dominant males when sperm are swimming in ovarian fluid. In sum, our result suggests that ovarian fluid increase sperm velocity more in dominant males than in subordinate males. Although this finding could partly be caused by cryptic female choice exerted by the ovarian fluid for sperm from dominant males, an alternative and more parsimonious explanation is that sperm from dominant males may simply be better designed for swimming in ovarian fluid compared to sperm from subordinate males. Thus, sperm production in the two reproductive roles seems to be adaptively tailored to different external environments

Dorsal Herniation of Cauda Equina Due to Sequestrated Intradural Disc

Intradural lumbar disc herniation (ILDH) is uncommon pathology. In present report, authors present a case of ILDH associated with dorsal herniation of the cauda equina rootlets in a 30-year-old male laborer who had chronic backache since last two years. To the best of our knowledge we are reporting this for first time. Report demonstrates the natural course of ILDH