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Recent papers describe successful Single-Trip Completions (STC) operations carried out offshore Nigeria and other locations and has successfully shed light on implementation of this advanced technology, which represents a step change in operational efficiency. However, the cost of these STC equipment may be prohibitive for wells drilled in shelf or swamp environments. The delivery of STC relies on different communication methods to communicate with and function the down-hole tools that make up part of the STC assemblies such as the "hydraulically actuated sand screens", the "radio frequency identification (RFID) actuated sleeves", and "valves". These different communication methods permit the running of a closed-loop system to ensure well integrity through-out the deployment and commissioning of the completion system. This paper will discuss pre-job planning, field execution and lessons learned from technologies developed to fit this environment while simultaneously challenging conventional thinking around open hole and cased hole completions systems, while addressing the operator's key drive towards capital efficiency through reduction of rig-days by as much as 50%. While several of the components incorporated in the STC system had been run previously in isolation, this paper will discuss the steps taken to facilitate the first full system approach to the application of sand screens fitted with hydro-mechanical inflow control device sleeves designed to actuate on pressure bleed-off, RFID enabled tools in the first hybrid single trip interventionless sand control completion system, and the time savings realized while ensuring well integrity through-out the deployment. Several components within the completion system have been equipped with novel enabling technology, RFID operated reservoir isolation valve at toe of the completion, wire wrapped sand screens fitted with hydro-mechanical sleeves designed to actuate on pressure bleed down complete with inflow control devices, and fuse actuated remote operated circulating sleeves for annular fluid displacement, which will all be discussed within.

Evolutionary biologists have long trained their sights on adaptation, focusing on the power of natural selection to produce relative fitness advantages while often ignoring changes in absolute fitness. Ecologists generally have taken a different tack, focusing on changes in abundance and ranges that reflect absolute fitness while often ignoring relative fitness. Uniting these perspectives, we articulate various causes of relative and absolute maladaptation and review numerous examples of their occurrence. This review indicates that maladaptation is reasonably common from both perspectives, yet often in contrasting ways. That is, maladaptation can appear strong from a relative fitness perspective, yet populations can be growing in abundance. Conversely, resident individuals can appear locally adapted (relative to nonresident individuals) yet be declining in abundance. Understanding and interpreting these disconnects between relative and absolute maladaptation, as well as the cases of agreement, is increasingly critical in the face of accelerating human-mediated environmental change. We therefore present a framework for studying maladaptation, focusing in particular on the relationship between absolute and relative fitness, thereby drawing together evolutionary and ecological perspectives. The unification of these ecological and evolutionary perspectives has the potential to bring together previously disjunct research areas while addressing key conceptual issues and specific practical problems.

This paper will portray the development and deployment of remote-activated sliding sleeve devices commissioned for use in a two-stage completion North Sea project. The sliding sleeves are required within the lower completion to provide access to the reservoir, protection to a control line and act as part of the fluid-loss envelope. Remote activation technology has been implemented to the sleeve designs to improve efficiency and introduce operational flexibility. Three variants of sleeves were designed and deployed to facilitate well objectives. The first variant is run-in-hole (RIH) Open to provide a circulation path and subsequently closed post displacement activities. The second variant is RIH Closed and is distributed across the reservoir. These sleeves are remotely opened post Xmas tree installation and provide the tubing/annulus communication for production or injection. The third variant is again RIH Closed, but this is a purely mechanical sleeve to allow further access to compartments or different reservoir units later in the well's life. A variant of open-hole anchor with bypass capability was also developed and tested. Remote-activated sliding sleeves were prototyped and qualified to API 19AC. In addition to the standard requirements of API 19AC, open/close cycles were also performed with lost circulation material-laden (LCM) fluid along with low hydrostatic pressure function testing. This latter testing is to allow for sequential functioning without having to shut in or choke back the well, instead functioning while the well is flowing or even under full operational drawdown. Three wells have been completed to date, two producers and one injector. The RIH Open sleeves have successfully acted as a replacement to a traditional fluid loss valve and the RIH Closed sleeves have allowed zonal isolation, selective water shut-off and reservoir management. The use of open-hole anchors has also been standardised, in producers to support future stimulation operations and in injectors to combat thermal contraction. Across all three wells the RIH Open sleeves have all been actuated successfully via Radio Frequency Identification (RFID) tag carrier or timer and the RIH Closed via pressure sequence and / or timer. The second producer also saw the first implementation of the staged clean-up functionality with sleeves opening at four different intervals over a period of 17 days.

Curvature tensors of higher-spin gauge theories have been known for some time. In the past, they were postulated using a generalization of the symmetry properties of the Riemann tensor (curl on each index of a totally symmetric rank-$n$ field for each spin-$n$). For this reason they are sometimes referred to as the generalized 'Riemann' tensors. In this article, a method for deriving these curvature tensors from first principles is presented; the derivation is completed without any a priori knowledge of the existence of the Riemann tensors or the curvature tensors of higher-spin gauge theories. To perform this derivation, a recently developed procedure for deriving exactly gauge invariant Lagrangian densities from quadratic combinations of $N$ order of derivatives and $M$ rank of tensor potential is applied to the $N = M = n$ case under the spin-$n$ gauge transformations. This procedure uniquely yields the Lagrangian for classical electrodynamics in the $N = M = 1$ case and the Lagrangian for higher derivative gravity (`Riemann' and `Ricci' squared terms) in the $N = M = 2$ case. It is proven here by direct calculation for the $N = M = 3$ case that the unique solution to this procedure is the spin-3 curvature tensor and its contractions. The spin-4 curvature tensor is also uniquely derived for the $N = M = 4$ case. In other words, it is proven here that, for the most general linear combination of scalars built from $N$ derivatives and $M$ rank of tensor potential, up to $N=M=4$, there exists a unique solution to the resulting system of linear equations as the contracted spin-$n$ curvature tensors. Conjectures regarding the solutions to the higher spin-$n$ $N = M = n$ are discussed., 12 pages

It is often stated that necessity is the mother of invention. Never is this proverb more relevant than in the offshore oil and gas environment we currently operate in where real step changes leading to reduced capital and operational expenditure opportunities are sought and embraced by field operators. This paper discusses the pre-job planning, field execution and lessons learned from one such technology that challenged conventional thinking of sand faced completion, casedhole completion and well integrity to successfully deliver a single-trip, interventionless, sand control completion in deepwater Bonga Field, located on the continental slope of the Niger Delta. Convention dictates that the vast majority of offshore completions be run in two and sometimes three trips which routinely takes in excess of eight to ten days to deploy. Given the day rate of high specification rigs capable of drilling in deep water environments, the ability to reduce this time was deemed paramount to the economics of the project. Utilizing a collaborative approach to initial concept design, risk assessment, extensive testing and contingency planning at component and system level, a single-trip, interventionless, sand control completion system was designed and successfully installed. This paper describes the completion architecture, operational sequence and challenges leading to the installation of an interventionless completion. A clearly defined set of deliverables and design principles were drawn up to guide the direction of the project including: successfully deploying the upper and lower completion in one trip, and testing all barriers. Adopting a simple, low risk and high reward design, meeting clients well barrier requirements and utilizing proven cost-effective technology are examples of design principles used. The system was tested and evolved through a number of iterations in an onshore trial well environment on a number of occasions leading to the first successful deployment completed in the second half of 2018, resulting in an average completion installation time of 5 days, versus the average 10 days for deploying multi-trip completions. Details of the successful installations, lessons learned, along with planned future activity are outlined within the body of this paper. While several of the components incorporated in the single-trip system had been run previously in isolation, this paper also discusses the steps taken to facilitate the first full-system approach to the application of radio frequency identification (RFID) enabled tools in the first single-trip, interventionless sand control completion system. Several components within the completion have been equipped with this technology including a multi-cycle ball valve, wire wrapped screens fitted with inflow control device (ICD), remote operated sliding sleeve for annular fluid displacement.

Monitoring trace metal and metalloid concentrations in marine animals is important for their conservation and could also reliably reflect pollution levels in their marine ecosystems. Concentrations vary across tissue types, with implications for reliable monitoring. We sampled blood and moulted feathers of the Little Penguin (Eudyptula minor) from three distinct colonies, which are subject to varying levels of anthropogenic impact. Non-essential trace metal and metalloid concentrations in Little Penguins were clearly linked to the level of industrialisation adjacent to the respective foraging zones. This trend was more distinct in blood than in moulted feathers, although we found a clear correlation between blood and feathers for mercury, lead and iron. This study represents the first reported examination of trace metals and metalloids in the blood of any penguin species and demonstrates that this high trophic feeder is an effective bioindicator of coastal pollution.

Driven by ever increasing associated costs, the industry has long sought an enabling technology to expedite hydraulic fracture cycle times in high cost environments such as offshore. Remotely operated completion tools have been proven to provide these efficiencies and can positively influence the viability of these multi-zone stimulation projects.This paper will focus on the planning and execution of an offshore North Sea lower completion to present a methodology to remotely access and isolate the reservoir during multi-zone stimulation operations. Innovative technologies utilized in this case study are presented which effectively minimize the cycle time of the stimulation process while providing a high level of contingencies to account for a panoply of scenarios which could occur through-out the operation.There are several techniques and methodologies which have been deployed to efficiently stimulate multi-zone, horizontal wells in offshore locations such as those found in the North Sea; technical papers such as (Langford 2014) discuss these in detail. This paper will describe the successful deployment of a novel lower completion system into a Southern North Sea extended reach well in June 2015 which targeted the a sandstone formation of the Lower Permian (Rotliegend) strata.The selected remotely operated lower completion system incorporates multiple communication methods on-board to permit remote functioning of flapper isolation valves, to compartmentalize the reservoir internally, and remote operated stimulation sleeves to access the reservoir, which effectively eliminates the need for intervention between treatments, ultimately improving fracture cycle time and reducing risk while providing operators with realistic contingencies in the event of screen-out.

This paper documents our campaign to undertake the large-scale optical character recognition of ancient, or polytonic, Greek. Building upon the Gamera OCR engine and developing a suite of post-processing tools, including automatic spellcheck, we processed 1,200 volumes comprising 329,002,271 Greek words. A sample of 10 pages is studied in detail; they demonstrate the degree to which each step of post-processing improved the results, and with which source documents. These pages attain an average character accuracy of about 96%. These results will provide a basis for further improvements, including the training of other open-source OCR engines.

Driven by ever increasing associated costs, the industry has long sought an enabling technology to expedite hydraulic fracture cycle times in high cost environments such as offshore. Remotely operated completion tools have been proven to provide these efficiencies and can positively influence the viability of these multi-zone stimulation projects. This paper will focus on the planning and execution of a recently completed offshore North Sea lower completion to present a methodology to remotely access and isolate the reservoir during multi-zone stimulation operations. Innovative technologies utilized in this case study are presented which effectively minimize the cycle time of the stimulation process while providing a high level of contingencies to account for a panoply of scenarios which could occur through-out the operation. There are several techniques and methodologies which have been deployed to efficiently stimulate multi-zone, horizontal wells in offshore locations such as those found in the North Sea; technical papers such as (Langford 2014) discuss these in detail. This paper will describe the successful deployment of a novel lower completion system into a Southern North Sea extended reach well in June 2015 which targeted the a sandstone formation of the Lower Permian (Rotliegend) strata. The selected remotely operated lower completion system incorporates multiple communication methods on-board to permit remote functioning of flapper isolation valves, to compartmentalize the reservoir internally, and remote operated stimulation sleeves to access the reservoir, which effectively eliminates the need for intervention between treatments, ultimately improving fracture cycle time and reducing risk while providing operators with realistic contingencies in the event of screen-out.

This case uses first-person sources to put the reader inside the teams that developed and marketed the Firefox browser. A brief overview of the Open Source Software (OSS) development process and the various roles played by members of a software development community, as well as a brief summary of the browser wars of the 1990s that saw Netscape Navigator fall from the dominant browser in the market to a distant second place behind Microsoft's Internet Explorer, help provide context for the case. In order to adapt the OSS development model to support a consumer-oriented product, Firefox developers adopted four rules: ‘We want it to be small,’ ‘Let's not keep too many cooks,’ ‘All patches are not created equal,’ and ‘All users are not created equal.’ The development team established a goal of 10 million downloads in the first 100 days and a 10% market share in the first year as measures of success for the new browser. In order to compete with Microsoft in the browser market, the Firefox team needed to leverage the development community to reach millions of potential end users. By providing a web-based structure for collaboration, and through a series of top-down initiatives (providing marketing tools to the community), and bottom-up initiatives (receiving and disseminating marketing ideas from the community at large), the team was able to achieve its marketing goals. In so doing, the SpreadFirefox initiative created a marketing community with roles analogous to a software development community.

Quantifying sessile marine invertebrate recruitment often requires destructive sampling or extrapolation from artificial substrata, the latter introducing the danger of artifacts. We measured intertidal mussel recruitment into mussel beds and into brushes at three-month intervals for five years across 3,200 km of southern Africa and determined substrata effects on recruitment rate. Recruitment into mussel beds showed a strong, coast-wide gradient, with high recruitment on the West coast, diminishing on the South coast, and increasing slightly on the East coast. At scales of 10 s of km, brushes reflected natural temporal recruitment variability, with a strong significant linear correlation between recruitment into brushes and into mussel beds. However, the relationship became semi-logarithmic when comparing among locations at a scale of 100 s of km. Artificial substrata thus reflect local natural settlement well but may be a poor indicator of it when spatial scales are large, particularly when mussel bed topography is complex, or localities have very different recruitment densities.

The rotary subwoofer is a novel low frequency transducer capable of efficiently generating infrasound from a compact source. A field-deployable version of this device may find application as a calibration source for infrasound arrays of the International Monitoring System (IMS) [(2001). The Global Verification Regime and the International Monitoring System (CTBTO Preparatory Commission Vienna International Centre, Vienna, Austria)]. A prototype tested at the IMS infrasound array I59US demonstrated the ability to insonify all elements of the array from a standoff distance of 3.8 km. Signal-to-noise ratios of continuous wave signals ranged from 5 to 15 dB, indicating the utility of this source to transmit controllable infrasound signals over distances of 5 km.

A novel openhole packer system was developed and successfully field deployed following an extensive development and testing program. A gap within the industry was identified by two operators who determined that assured zonal isolation was a key requirement for future field developments. A design study was undertaken to determine possible sealing solutions. The intial concepts were adaptations of cased-hole technology that were confirmed to be inappropriate. A cup seal element system actuated by an innovative deployment system capable of handling variances in hole size and hole irregularities without excessively stressing the near well bore region was found to offer a robust sealing solution. A qualification program was developed and the packer has been field deployed successfully in a number of geographic locations.

The South Kensington Museum—now the Victoria and Albert Museum—has a complex history. Founded in 1857 as an omnibus museum of art and industry—a condensation of the Great Exhibition of 1851 in all its abundance—it had a bewildering variety of possible futures ahead of it, including failure (or existence as an adjunct to a café, as one infamous ad campaign suggested twenty years ago).2 Yet the history of the museum has generally been written teleologically and typologically, as though it were both inevitable and obvious that it should turn into an art museum. The figure behind this foregone development is Henry Cole (aided by a few of his curators), who is perceived as rather quickly subjugating the conflicting possible directions of the museum to the goal of making art available for the public. I would like to offer a sketch of a different history here, one that sees the context of the museum not in the field of other like museums but in its location, both physical and institutional, on the land owned by the Commissioners of the Great Exhibition of 1851 and in the Education Department.

This study uses social network analysis to examine distributed leadership in work teams. We used sociometric data from 28 field-based sales teams to investigate how the network structure of leadership perceptions considered at the team level of analysis was related to team performance. We failed to find support for the idea that the more leadership is distributed across the members of a team the better the team's performance: Decentralization of the leadership network (across three different operationalizations of network decentralization) was not significantly related to superior team performance. But we did find support for the idea that certain kinds of decentralized leadership structures are associated with better team performance than others. Our study suggests that distributed leadership structures can differ with regard to important structural characteristics, and these differences can have important implications for team performance.

Understanding the similarities and differences between the research priorities of academics and those of practitioners may create opportunities for mutually beneficial collaboration. We used a three-phase process to tap industry forward thinkers to identify 40 research topics of import to practitioners in the financial services industry. These topics were refined and validated, leaving 15 areas where research needs are a top priority. We mapped these areas against two published academic research agendas to identify areas of convergence and divergence. Our findings suggest that more than half of academic research falls into areas deemed important by practitioners in this industry. We pinpoint four areas particularly vital to practitioners where little academic research exists. We discuss tailored approaches for developing collaborative research for high-convergence areas versus for low-convergence areas.