73,729 research outputs found
Indigenous Environmental Network v. United States Department of State
Pipelines are an extremely efficient way to move large amounts of oil and gas across long distances. However, pipelines have become a lightning rod for environmentalists opposing the lines’ construction and the energy sector which considers the lines a must to achieve energy independence and security. Pipelines are massive projects often crossing interstate and international boundaries. As a result, they are subject to an extensive amount of government regulation with an accompanying assortment of legal challenges. Indigenous Environmental Network v. United States Department of State is the latest case in the Keystone XL pipeline saga, wherein the United States District Court for the District of Montana found several procedural insufficiencies with the Department’s actions in approving the pipeline
Computational Fluid Dynamics Based Optimal Design of Hydraulic Capsule Pipelines Transporting Cylindrical Capsules
Rapid depletion of energy resources has immensely affected the transportation sector, where the cargo transportation prices are rising considerably each year. Efforts have been made to develop newer modes of cargo transportation worldwide that are both economical and efficient for a long time. One such mode is the use of energy contained within fluids that flows in the pipelines for transportation of bulk solids. After appropriate modifications to these pipelines, bulk solids can be transported from one location to another very effectively. Solid material can be stored in cylindrical containers (commonly known as capsules), which can then be transported, either singly or in a train through the pipeline. Both the local flow characteristics and global performance parameters associated with such pipelines need careful investigation for economical and efficient system design. Published literature is severely limited in establishing the effects local flow features on system characteristics of Hydraulic Capsule Pipelines (HCPs). The present study focuses on using a well validated Computational Fluid Dynamics (CFD) tool to numerically simulate the solid-liquid mixture flow in HCPs, installed both on-shore and off-shore, along-with the pipe bends. Local static pressure fields have been discussed in detail for a wide range of geometrical and flow related parameters associated with the capsules and the pipelines. Numerical predictions have been used to develop novel semi-empirical prediction models for pressure drop in HCPs, which have then been embedded into a pipeline optimisation methodology that is based on Least-Cost Principle. This novel optimisation methodology that has been developed for HCPs is both robust and user-friendly
High-throughput Binding Affinity Calculations at Extreme Scales
Resistance to chemotherapy and molecularly targeted therapies is a major
factor in limiting the effectiveness of cancer treatment. In many cases,
resistance can be linked to genetic changes in target proteins, either
pre-existing or evolutionarily selected during treatment. Key to overcoming
this challenge is an understanding of the molecular determinants of drug
binding. Using multi-stage pipelines of molecular simulations we can gain
insights into the binding free energy and the residence time of a ligand, which
can inform both stratified and personal treatment regimes and drug development.
To support the scalable, adaptive and automated calculation of the binding free
energy on high-performance computing resources, we introduce the High-
throughput Binding Affinity Calculator (HTBAC). HTBAC uses a building block
approach in order to attain both workflow flexibility and performance. We
demonstrate close to perfect weak scaling to hundreds of concurrent multi-stage
binding affinity calculation pipelines. This permits a rapid time-to-solution
that is essentially invariant of the calculation protocol, size of candidate
ligands and number of ensemble simulations. As such, HTBAC advances the state
of the art of binding affinity calculations and protocols
Productivity and Efficiency of US Gas Transmission Companies: A European Regulatory Perspective
Keywords JEL Classification On both sides of the Atlantic the regulation of gas transmission networks has undergone major changes since the early 1990’s. Whereas in the US the long-standing regime of cost-plus regulation was complemented by increasing pipe-to-pipe competition, most European countries moved towards incentive regulation complemented by market integration. We study the impact of US regulatory reform using a Malmquist-based productivity analysis for a panel of US interstate companies. Results are presented for changes in productivity, as well as for several convergence tests. The results indicate that taking productivity and convergence as performance indicators, regulation has been rather successful, in particular during a period where overall demand was flat. Lessons for European regulators are twofold. First, the US analysis shows that benchmarking of European transmission operators would be possible if data were available. Second, our results suggest that, in the long-run, market integration and competition are alternatives to the current European model. Natural gas transmission; utility regulation; data envelopment analysis; total factor productivity; convergenc
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Strategic Eurasian Natural Gas Model for Energy Security
The mathematical formulation of a large-scale equilibrium natural gas simulation model is presented. Although large-scale natural gas models have been developed and used for energy security and policy analysis quite extensively (e.g., Holz (2007), Egging et al. (2008), Holz et al. (2009) and Lise et al. (2008)), this model differs from earlier ones in its detailed representation of the structure and operations of the Former Soviet Union (FSU) gas sector. In particular, the model represents: (i) market power of transit countries, (ii) transmission pipelines in Russia, Ukraine, Belarus and Central Asia, (iii) differentiation among gas production regions in Russia, and (iv) gas trade relations between FSU countries (e.g., Gazprom’s re-exporting of Central Asian gas). To demonstrate the model, a social benefit-cost analysis of the Nord Stream gas pipeline project from Russia to Germany via the Baltic Sea is provided. It is found that Nord Stream project is profitable for its investors and the project also improves social welfare in all market power scenarios. Also, if transit countries (Ukraine and Belarus) exert substantial market power then the economic value of Nord Stream to its investors and to society improves substantially. We also found that the value of Nord Stream investment is rather sensitive to the degree of downstream competition in European markets and that lack of downstream competition might result in the negative value of the Nord Stream system to Gazprom
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