Ground cracking and frost heaving associated with chilled gas pipeline operations in Britain

This thesis investigates the soil-pipeline interactions associated with the operation of large-diameter chilled gas pipelines in Britain, these are frost/pipe heave and ground cracking. The investigation was biased towards the definition of the mechanism of ground cracking and, the parameters which influence its generation and subsequent development, especially its interaction with frost heave. The study involved a literature review, questionnaire, large-scale test and small-scale laboratory model experiments. The literature review concentrated on soil-pipeline interactions and frost action, with frost/pipe heave often reported but ground cracking was seldom reported. A questionnaire was circulated within British Gas to gain further information on these interactions. The replies indicated that if frost/pipe heave was reported, ground cracking was also likely to be observed. These soil-pipeline interactions were recorded along 19% of pipelines in the survey and were more likely along the larger diameter, higher flow pipelines. A large-scale trial along a 900 mm pipeline was undertaken to assess the soil thermal, hydraulic and stress regimes, together with pipe and ground movements. Results indicated that cracking occurred intermittently along the pipeline during periods of rapid frost/pipe heave and ground movement and, that frozen annulus growth produced a ground surface profile was approximated by a normal probability distribution curve. This curve indicates maximum tensile strain directly over the pipe centre. Finally a small-scale laboratory model was operated to further define the ground cracking mechanism. Ground cracking was observed at small upward ground surface movement, and with continued movement the ground crack increased in width and depth. At the end of the experiments internal soil failure planes slanting upwards and away from the frozen annulus were noted. The suggested mechanism for ground cracking involved frozen annulus growth producing tensile strain in the overlying unfrozen soil, which when sufficient produced a crack.

Evaluation and development of drainage and pipeline construction processes

In 1974 Dr D M Bramwell published his research work at the University of Aston a part of which was the establishment of an elemental work study data base covering drainage construction. The Transport and Road Research Laboratory decided to, extend that work as part of their continuing research programme into the design and construction of buried pipelines by placing a research contract with Bryant Construction. This research may be considered under two broad categories. In the first, site studies were undertaken to validate and extend the data base. The studies showed good agreement with the existing data with the exception of the excavation trench shoring and pipelaying data which was amended to incorporate new construction plant and methods. An inter-active on-line computer system for drainage estimating was developed. This system stores the elemental data, synthesizes the standard time of each drainage operation and is used to determine the required resources and construction method of the total drainage activity. The remainder of the research was into the general topic of construction efficiency. An on-line command driven computer system was produced. This system uses a stochastic simulation technique, based on distributions of site efficiency measurements to evaluate the effects of varying performance levels. The analysis of this performance data quantities the variability inherent in construction and demonstrates how some of this variability can be reconciled by considering the characteristics of a contract. A long term trend of decreasing efficiency with contract duration was also identified. The results obtained from the simulation suite were compared to site records collected from current contracts. This showed that this approach will give comparable answers, but these are greatly affected by the site performance parameters.

Relieving the first bottleneck in the drug discovery pipeline:using array technologies to rationalize membrane protein production

The slow down in the drug discovery pipeline is, in part, owing to a lack of structural and functional information available for new drug targets. Membrane proteins, the targets of well over 50% of marketed pharmaceuticals, present a particular challenge. As they are not naturally abundant, they must be produced recombinantly for the structural biology that is a prerequisite to structure-based drug design. Unfortunately, however, obtaining high yields of functional, recombinant membrane proteins remains a major bottleneck in contemporary bioscience. While repeated rounds of trial-and-error optimization have not (and cannot) reveal mechanistic details of the biology of recombinant protein production, examination of the host response has provided new insights. To this end, we published an early transcriptome analysis that identified genes implicated in high-yielding yeast cell factories, which has enabled the engineering of improved production strains. These advances offer hope that the bottleneck of membrane protein production can be relieved rationally.

Pathways to leadership:board independence, diversity, and the emerging pipeline in the US for women directors

In the wake of this decade's corporate scandals, crimes and excesses, improving the effectiveness of corporate governance in the United States has become a priority. An important influence on a board's effectiveness at monitoring is its members’ degree of independence from senior management. While the current definition of independence revolves around the absence of familial and economic connections between a firm and its directors, research suggests that this standard may be inadequate in ensuring independent oversight. Rather, diversity along racial, gender and other dimensions has been proposed as a potentially more effective standard for board independence. This is especially welcome news for women, who currently comprise 51 per cent of the US managerial workforce but only 14.8 per cent of the directors on boards of large, publicly traded US corporations. Some explain the current dearth of women board members by claiming that there are no qualified women available for board service and/or that women are not interested in board service. However, there is more anecdotal rather than empirical evidence on the issue. Surveying women at a women's leadership conference in Boston, this research investigates the extent to which women are currently involved in some type of board service and the extent to which women aspire to future board service. We find that women are currently more active in governance activities than prior research on corporate boards suggests and that they aspire to play a continued and expanded role in governance activities.

Risk-based model aids selection of pipeline inspection, maintenance strategies

The existing method of pipeline monitoring, which requires an entire pipeline to be inspected periodically, wastes time and is expensive. A risk-based model that reduces the amount of time spent on inspection has been developed. This model not only reduces the cost of maintaining petroleum pipelines, but also suggests an efficient design and operation philosophy, construction method and logical insurance plans.The risk-based model uses analytic hierarchy process, a multiple attribute decision-making technique, to identify factors that influence failure on specific segments and analyze their effects by determining the probabilities of risk factors. The severity of failure is determined through consequence analysis, which establishes the effect of a failure in terms of cost caused by each risk factor and determines the cumulative effect of failure through probability analysis.

Decision support system for pipeline route selection

Presents information on a study which proposed a decision support system (DSS) for a petroleum pipeline route selection with the application of analytical hierarchy process. Factors governing route-selection for cross-country petroleum pipelines; Application of the DSS from an Indian perspective; Cost benefit comparison of the shortest route and the optimal route; Results and findings.

Hierarchical approach to project planning:the case of a petroleum pipeline construction

Projects exposed to an uncertain environment must be adapted to deal with the effective integration of various planning elements and the optimization of project parameters. Time, cost, and quality are the prime objectives of a project that need to be optimized to fulfill the owner's goal. In an uncertain environment, there exist many other conflicting objectives that may also need to be optimized. These objectives are characterized by varying degrees of conflict. Moreover, an uncertain environment also causes several changes in the project plan throughout its life, demanding that the project plan be totally flexible. Goal programming (GP), a multiple criteria decision making technique, offers a good solution for this project planning problem. There the planning problem is considered from the owner's perspective, which leads to classifying the project up to the activity level. GP is applied separately at each level, and the formulated models are integrated through information flow. The flexibility and adaptability of the models lies in the ease of updating the model parameters at the required level through changing priorities and/or constraints and transmitting the information to other levels. The hierarchical model automatically provides integration among various element of planning. The proposed methodology is applied in this paper to plan a petroleum pipeline construction project, and its effectiveness is demonstrated.

Petroleum pipeline construction planning:a conceptual framework

A cross-country pipeline construction project is exposed to an uncertain environment due to its enormous size (physical, manpower requirement and financial value), complexity in design technology and involvement of external factors. These uncertainties can lead to several changes in project scope during the process of project execution. Unless the changes are properly controlled, the time, cost and quality goals of the project may never be achieved. A methodology is proposed for project control through risk analysis, contingency allocation and hierarchical planning models. Risk analysis is carried out through the analytic hierarchy process (AHP) due to the subjective nature of risks in construction projects. The results of risk analysis are used to determine the logical contingency for project control with the application of probability theory. Ultimate project control is carried out by hierarchical planning model which enables decision makers to take vital decisions during the changing environment of the construction period. Goal programming (GP), a multiple criteria decision-making technique, is proposed for model formulation because of its flexibility and priority-base structure. The project is planned hierarchically in three levels—project, work package and activity. GP is applied separately at each level. Decision variables of each model are different planning parameters of the project. In this study, models are formulated from the owner's perspective and its effectiveness in project control is demonstrated.

Planning for project control through risk analysis:a case of petroleum pipeline laying

Projects that are exposed to uncertain environments can be effectively controlled with the application of risk analysis during the planning stage. The Analytic Hierarchy Process, a multiattribute decision-making technique, can be used to analyse and assess project risks which are objective or subjective in nature. Among other advantages, the process logically integrates the various elements in the planning process. The results from risk analysis and activity analysis are then used to develop a logical contingency allowance for the project through the application of probability theory. The contingency allowance is created in two parts: (a) a technical contingency, and (b) a management contingency. This provides a basis for decision making in a changing project environment. Effective control of the project is made possible by the limitation of the changes within the monetary contingency allowance for the work package concerned, and the utilization of the contingency through proper appropriation. The whole methodology is applied to a pipeline-laying project in India, and its effectiveness in project control is demonstrated.

Overcoming bottlenecks in the membrane protein structural biology pipeline

Membrane proteins account for a third of the eukaryotic proteome, but are greatly under-represented in the Protein Data Bank. Unfortunately, recent technological advances in X-ray crystallography and EM cannot account for the poor solubility and stability of membrane protein samples. A limitation of conventional detergent-based methods is that detergent molecules destabilize membrane proteins, leading to their aggregation. The use of orthologues, mutants and fusion tags has helped improve protein stability, but at the expense of not working with the sequence of interest. Novel detergents such as glucose neopentyl glycol (GNG), maltose neopentyl glycol (MNG) and calixarene-based detergents can improve protein stability without compromising their solubilizing properties. Styrene maleic acid lipid particles (SMALPs) focus on retaining the native lipid bilayer of a membrane protein during purification and biophysical analysis. Overcoming bottlenecks in the membrane protein structural biology pipeline, primarily by maintaining protein stability, will facilitate the elucidation of many more membrane protein structures in the near future.

Against all odds: Success stories of Latino students who survived the educational pipeline

The purpose of this interview study was to explore the experiences of Latino students, from their perspectives, as they journeyed through the educational pipeline, particularly the part focusing on the transfer experience from a 2-year college to a 4-year institution. This was accomplished by conducting in-depth interviews with 17 self-identified Latino men and women. All of the participants had attended Florida International University for at least 1 semester and had transferred from Miami Dade College. The participants varied in age, generational status, and cultural identity.^ The participants were asked to reflect on the external and internal influences that lead them to the 4-year institution. Tinto's (1993) model of student departure theory provided the theoretical framework for data collection and analysis. Based on the coding of the interviews, numerous themes emerged, including the role of the family, the impact of early education, the experiences of being Latino in Miami, the decisions to choose a college, the experience at the 2-year institution, the experience with the transfer process, and the obstacles and strategies the participants used for overcoming obstacles. These themes were furthered developed to determine which influences were most important for a successful journey through the educational pipeline. ^ The study found that viewing the pipeline via the students' perspectives juxtaposed with Tinto's (1993) model of student departure gave greater insight into the experiences of a population of students who have been underrepresented in higher education. The findings of this case study indicate that the transfer process for Latinos attending a Hispanic Serving Institution such as Florida International University, situated in a majority-minority city, is complex, with participants having to rely on peers and significant others for pertinent information and support. Several factors, including the importance of positive support networks and increased confidence nurtured by the 2-year institution, influenced the students' transfer to a 4-year institution. For professionals in the field, the findings of this study may lead to a broader understanding of the experiences of Latino students in the pipeline and, more importantly, assist college administrators and faculty in successfully guiding a population through a 4-year institution who first came via a 2-year institution. ^