Traditionally, researchers in decision making have focused on attempting to reach Pareto Optimality using horizontal approaches, where optimality is calculated taking into account every participant at the same time. Sometimes, this may prove to be a difficult task (e.g., conflict , mistrust, no information sharing, etc.). In this paper, we explore the possibility of achieving Pareto Optimal outcomes in a group by using a bottom-up approach: discovering Pareto optimal outcomes by interacting in subgroups. We analytically show that Pareto optimal outcomes in a subgroup are also Pareto optimal in a supergroup of those agents in the case of strict , transitive, and complete preferences. Then, we empirically analyze the prospective usability and practicality of bottom-up approaches in a variety of decision making domains.

There is a demand in the industry for coiled tubing (CT) that can safely reach significantly farther in horizontal wells than the current, steel based technology can reach. Some have suggested that CT composed of lighter materials could maintain a neutral or positive buoyancy (floating) in the horizontal section and thus be capable of reaching extraordinary total depths without exceeding their yield limit. However, several other aspects of CT operations must be considered for a complete assessment of extended reach capability, and these aspects often cause lighter materials to friction lock at shallow depths relative to their steel counterparts. Using a parametric analysis, this paper will quantify the effect material properties, including stiffness and density, have on CT performance in extended reach wells. It will also correlate those properties with materials available today such as steel, titanium, and composites to explain why steel tubing is used in most CT operations.

The objective of this 24 month project focused on improving microhole coiled tubing drilling bottom hole assembly (BHA) reliability and performance, while reducing the drilling cost and complexity associated with inclined/horizontal well sections. This was to be accomplished by eliminating the need for a downhole drilling tractor or other downhole coiled tubing (CT) friction mitigation techniques when drilling long (>2,000 ft.) of inclined/horizontal wellbore. The technical solution to be developed and evaluated in this project was based on vibrating the coiled tubing at surface to reduce the friction along the length of the downhole CT drillstring.

There are aspects of pipe behavior and limits that can be confusing and counter intuitive. These include understanding the conditions under which a pipe will "buckle" and when the stresses in the pipe will reach a point where the pipe material "yields". The combination of forces, pressures, torque and bending moments that are being applied to the pipe may make it difficult to understand how the pipe will responding. The objective of this paper is to clarify some of these issues and demonstrate a simplified calculation tool for field engineers to use when critical decisions need to be made quickly.

In recent years there have been a significant number of coiled tubing (CT) failures during frac-plug drill-out operations. These failures occur most often when an axial vibration/pulsation extended reach tool (ERT) is included in the bottom hole assembly (BHA). There are significant efforts in the industry to first understand and then mitigate these failures. This paper examines the dynamic axial vibrations caused by these tools, and how these vibrations are amplified in the wellbore, possibly causing the material damage that later causes the failures. In some cases, these amplified vibrations have damaged surface equipment.