bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successful Use of Real Time Dynamic Flow Modelling to Control a Very Challenging Managed Pressure Drilling Operation in the North Sea
Authors: Bjørkevoll Knut Steinar , Hovland Svein , Aas Ingvill Barr , Vollen Elin 
Published: February 2010

AbstractAn advanced dynamic flow and temperature model was used to optimize and control MPD operations in real time on the Gullfaks field in the North Sea. The well to be drilled only had a 7 bar window between the pore and fracture pressure according to prognosis. However, drilling objectives were eventually fulfilled aided by very accurate downhole pressure control. This paper addresses the model specific challenges, analyzes the differences between model calculations and downhole pressure data, and discusses how to bring hydraulic modelling further in accordance with future operational needs.Challenges related to how to tune the system efficiently and accurately, data quality issues, displacement operations, etc., are described and enlightened by downhole memory data made available when the string was back on surface. Ideas on how to build a more robust and easy to use system without sacrificing the advantages of having a high fidelity model in the real time loop are discussed.The experience and ideas described contribute to the development of a very accurate and reliable MPD system, which is capable of automatic pressure control during the whole sequence of drilling, tripping, circulation, displacements etc. An important goal for the future will be to reduce the offshore crew dedicated to the modelling function to a minimum, with the provision of onshore support during operations.
Measuring the Welfare Effects of Country of Origin Rules: A Suggested Methodology
Authors: Pelzman Joseph , Shoham Amir 
Published: February 2010

The United States and the European Union have generated dozens of bilateral Regional Trading Agreements (RTA) across the globe. All of these trading arrangements have detailed agreements on rules of origin (ROOs). Those rules are required in order to ensure that the perceived benefits of the Free Trade Agreements (FTA) are not subverted or deflected. These rules have their greatest impact on a firm's cost structure when applied to the trade of intermediate goods. Determination of the origin of final goods becomes more complicated where imported intermediates are used and the WTO 'substantial transformation' rules are implemented. There is relatively little literature on the impact of these rules of origin on trade. (Cadot et al., 2006; Duttagupta and Panagariya, 2002; and Falvey and Reed, 1998, 2002). The existing literature hypothesizes that these rules can easily be used to restrict or suppress trade between countries, or to divert trade away from more efficient suppliers to less efficient ones. The empirical evidence to support the trade distortions is based on the number and complexity of the rules of origin. In order to determine the degree to which the post-RTA trade flows are indeed affected by ROO requires a micro-based review of increased transaction costs, rather than the number of rules. The intent of this paper is to suggest a formal methodology, which relies on the literature about tariff-equivalents, to evaluate rules of origin requirements. The suggested approach, applied at the 5-digit HS level will provide a more robust evaluation of ROOs. The suggested methodology could also be used to investigate the oft-asserted hypothesis that with time and reduced tariff barriers, the costs associated with ROOs will diminish.
The Obama Administration and Latin America: A "New Partnership for the Americas"
Authors: Moncarz Raul 
Published: February 2010

Every new U.S. administration brings renewed hope and vigor to the World regarding unrealized dreams and aspirations as well as unfinished and not realized agendas. The U.S. has not neglected Latin America, even according to some the region has probably benefited from U.S. involvement in the Middle East and Afghanistan. A New Partnership for the Americas is the name that the Obama group used during the election campaign. The common thread is a preference to develop cooperation through converging national interests as articulated by the U.S. and Latin American Caribbean governments. The U.S. and Cuban government officials are talking for the first time in years raising hopes for a thaw in long-icy relations. President Obama has granted Cuban-Americans the right to travel freely to Cuba and to send remittances there, and to give U.S. telecommunications companies the right to pursue business there represents a first step in trying for better relations. If the new Obama administration thought that a change in the rhetoric and tone would make the likes of Castro, Chavez and others see things the U.S. way, a new lesson was learned in that sometimes countries disagree simply because their goals are mutually exclusive. A year after Barack Obama became U.S. president, pledging "a new beginning" in relations with Cuba and wining praise from Fidel Castro, bitter rhetoric is once more flying between the two states. At the outset it has to be recognized that the U.S. government actually understands what is happening in Latin America. The U.S. policy is highly sophisticated and often seems more drastic on its understanding of what is happening than some or most of its critics. Looking at some people's history of the hemisphere it is remarkable and transformative that for the first time in many years, the U.S. does not seem to care much what happens in Latin America. In an interconnected world, power does not need to be a zero sum game, and nations need not fear the success of another. Cultivating spheres of cooperation--not competing spheres of influence--will lead to progress in the Caribbean and Latin America. Engagement meaning expanded cooperation with and the need to broaden policy efforts with the group of leftists rules countries such as Brazil, Bolivia, Chile, Ecuador, Nicaragua, Uruguay, Peru and Venezuela beyond the previous administration focus on regional economic integration through competitive liberalization.
Graph isomorphic discrete partially ordered sets and semimodularity
Authors: Csontóová Mária , Lihová Judita 
Published: February 2010

Abstract
In [RATANAPRASERT, C.—DAVEY, B.: Semimodular lattices with isomorphic graphs, Order 4 (1987), 1–13], the authors found conditions under which an isomorphism of graphs of discrete lattices transfers semimodularity. The main theorem of the present paper generalizes their result for discrete partially ordered sets.
On quasi-prime, weakly quasi-prime left ideals in ordered-Γ-semigroups
Authors: Hila Kostaq 
Published: February 2010

Abstract
In this paper we obtain and establish some important results in ordered Γ-semigroups extending and generalizing those for semigroups given in [PETRICH, M.: Introduction to Semigroups, Merill, Columbus, 1973] and for ordered semigroups from [KEHAYOPULU, N.: On weakly prime ideals of ordered semigroups, Math. Japon. 35 (1990), 1051–1056], [KEHAYOPULU, N.: On prime, weakly prime ideals in ordered semigroups, Semigroup Forum 44 (1992), 341–346] and [XIE, X. Y.—WU, M. F.: On quasi-prime, weakly quasi-prime left ideals in ordered semigroups, PU.M.A. 6 (1995), 105–120]. We introduce and give some characterizations about the quasi-prime and weakly quasi-prime left ideals of ordered-Γ-semigroups. We also introduce the concept of weakly m-systems in ordered Γ-semigroups and give some characterizations of the quasi-prime and weakly quasi-prime left ideals by weakly m-systems.
Generalized difference sequence space defined by |$$
\bar N
$$, p
k| summability and an Orlicz function in seminormed space
Authors: Bhardwaj Vinod , Bala Indu 
Published: February 2010

Abstract
The object of this paper is to introduce a new difference sequence space which arise from the notions of |$$
\bar N
$$, p
k| summability and an Orlicz function in seminormed complex linear space. Various algebraic and topological properties and certain inclusion relations involving this space have been discussed. This study generalizes results: [ALTIN, Y.—ET, M.—TRIPATHY, B. C.: The sequence space |$$
\bar N_p
$$|(M, r, q, s) on seminormed spaces, Appl. Math. Comput. 154 (2004), 423–430], [BHARDWAJ, V. K.—SINGH, N.: Some sequence spaces defined by |$$
\bar N
$$, p
n| summability, Demonstratio Math. 32 (1999), 539–546] and [BHARDWAJ, V. K.—SINGH, N.: Some sequence spaces defined by |$$
\bar N
$$, p
n| summability and an Orlicz function, Indian J. Pure Appl. Math. 31 (2000), 319–325].
Theorems for generalized Favard-Kantorovich and Favard-Durrmeyer operators in exponential function spaces
Authors: Nowak Grzegorz , Sikorska-Nowak Aneta 
Published: February 2010

Abstract
We consider the Kantorovich and the Durrmeyer type modifications of the generalized Favard operators and we prove some direct approximation theorems for functions f such that w
σ
f ∈ L
p(R), where 1 ≤ p ≤ ∞ and w
σ(x) = exp(−σx
2), σ > 0.
Elements Influencing Study Success
Authors: Jereb Eva 
Published: February 2010

Elements Influencing Study Success
Study success can be influenced by following factors: (i) social elements (social class position, parents' education, parents' profession, parents' income); (ii) student-related factors (motivation, aptitude, effort, IQ, time spend on study, opportunity to learn, pre-university education); (iii) quality of instruction (organisation, course material, communication, assignments, exams, grading, course outcomes); (iv) curriculum (number of courses, sequence of courses, test schedule, system-block or parallel); (v) government (grant, student accommodation). In the paper the influence of these factors on study success is presented. Social and academic integration are central aspects. In the research we found out that "social elements" greatly influence the decision to enrol, but have less influence on marks received and the duration of study. Grants also greatly influence study success. We were surprised when we found out that factors from the "quality of instruction" group can only explain 12.3% of the variance of exam results.
Teaching Scrum in Cooperation with a Software Development Company
Authors: Mahnič Viljan , Georgiev Strahil , Jarc Tomo 
Published: February 2010

Teaching Scrum in Cooperation with a Software Development Company
The increasing use of agile methods for software development creates the need for these methods to become part of the education of future computer and information science engineers. On the other hand, teaching these methods gives us an opportunity to verify individual agile concepts and their effectiveness. For that reason, project work is an appropriate and frequently used form of teaching that enables students to get acquainted with agile methods and, at the same time, provides case studies for evaluating individual agile concepts. We describe our approach to teaching the Scrum agile method, within the software technology course, in cooperation with a software development company. Students were taught through work on a real project for which a list of requirements was submitted by the company. A co-worker of this company participated throughout the teaching period playing the role of customer's representative. During their work, students consistently used the Scrum method and at the end of each iteration they evaluated their experience by means of a questionnaire. In the article, the Scrum method is presented first, then a description of work on the project is given and finally the results of the survey are described.
Stakeholder Approach and the Corporate Financial Performance
Authors: Blažek Ladislav , Částek Ondřej 
Published: February 2010

Stakeholder Approach and the Corporate Financial Performance
The following paper aims to describe the analysis and utilization of stakeholder approach, which was used in the research of the Research Centre for Competitiveness of Czech Economy. The stakeholder model was employed in the research to explain the behavior of enterprises and to find factors of competitiveness. Here we can find assessment of stakeholders' importance and its relationship to corporate financial performance with some chosen interfering factors, which is preceding step before assessment all potential factors of competitiveness using multi dimensional analysis. Also the achieved results are related to chosen international and Czech studies.
A snow sensor experiment in Dronning Maud Land, Antarctica
Authors: Granberg Hardy B. , Cliche Patrick , Mattila Olli-Pekka , Kanto Eija , Leppäranta Matti 
Published: February 2010

AbstractIn January 2000 nine snow sensors were deployed in Dronning Maud Land, Antarctica, along a 355 km transect from Kvitkuven near the shelf edge via the Finnish research station, Aboa, to the Amundsenisen plateau. The purpose was to test a sensor system for spatio-temporal variations in temperature across the snow–air interface and snow accumulation/ablation, which includes atmospheric net balance and migrating snow dunes. In the dry snow conditions, environmental static electricity interfered with data transfer; several sensors were disabled early, while the longest record reached 6 months. Along the main transect, the year 2000 mass balance ranged from 52 to 221 mm w.e., largely following spatial patterns seen by other researchers. The level increased toward the edge of the ice sheet; unloading of drifting snow as the slope flattens, rather than increased snowfall as previously thought, may be responsible for this. At the Högisen ice dome site the mass balance was 897 mm w.e., possibly due to unloading of wind-blown snow, as katabatic winds are locally forced uphill. This mechanism is important to maintain such topographic features along the Antarctic ice sheet margin. Major precipitation events occurred at 3–5 week intervals and much of the precipitation fell before mid-June. The daily signal in temperature disappeared after the autumn equinox, then the spectrum displayed a broad peak at synoptic frequencies. Potential temperature decreased towards the shelf edge, displaying a pattern consistent with strong inversions and suggesting that strong evaporative cooling is associated with the katabatic winds.
Dynamics of a small surge-type glacier using one-dimensional geophysical inversion
Authors: De Paoli Laetitia , Flowers Gwenn E. 
Published: February 2010

AbstractWe investigate the dynamics of a small surge-type valley glacier as part of a study to characterize glacier response to climate in the Donjek Range, southwest Yukon, Canada. Pole displacements were measured using kinematic GPS techniques during three consecutive summer field seasons. Measured surface velocities range from <10 m a−1over the lower 1500 m of the 5 km long glacier to a maximum of ∼25–35 m a−1over the upper 3500 m. Basal velocities along an approximate flowline are reconstructed from the measured surface velocities using inverse methods. Control tests are used to validate the inversion scheme, and sensitivity tests are performed to evaluate the influence of the flow-law coefficient, shape factor and longitudinal averaging length. Inversion of the real data shows that basal motion accounts for 50–100% of the total surface motion along the flowline. Based on these results, and several other lines of evidence, we suggest this glacier may be undergoing a slow surge.
Terminus dynamics at an advancing glacier: Taku Glacier, Alaska
Authors: Truffer Martin , Motyka Roman J. , Hekkers Michael , Howat Ian M. , King Matt A. 
Published: February 2010

AbstractTaku Glacier, Alaska, USA, is currently in the advance stage of the tidewater glacier cycle. We investigated the near-terminus dynamics by measuring surface velocities, surface elevation changes, ice thickness and ablation. Velocities vary on sub-daily, diurnal, seasonal and interannual timescales. Flowline modeling shows that the modeled surface velocities are sensitive to changes in till yield strength and thus effective basal pressures. The glacier bed deepens in the up-glacier direction and this imposes a minimum subglacial water pressure necessary for water to drain along the bed. In a simple model we impose water-pressure gradients based on phreatic surfaces of constant slopes to simulate the winter–summer transitions. This proves sufficient to explain an observed early-season switch from compressional to block flow. Velocities also vary between years. Changing basal conditions can result in lower horizontal velocities, which decrease the ice supply to the terminus and result in temporary surface lowering. But a decrease in ice flux to the terminus must lead to ice storage further upstream, and that ice mass will eventually reach the terminus. This can explain the observed episodic nature of terminus advance.
Sediment plume response to surface melting and supraglacial lake drainages on the Greenland ice sheet
Authors: Chu Vena W. , Smith Laurence C. , Rennermalm Asa K. , Forster Richard R. , Box Jason E. , Reeh Niels 
Published: February 2010

AbstractIncreased mass losses from the Greenland ice sheet and inferred contributions to sea-level rise have heightened the need for hydrologic observations of meltwater exiting the ice sheet. We explore whether temporal variations in ice-sheet surface hydrology can be linked to the development of a downstream sediment plume in Kangerlussuaq Fjord by comparing: (1) plume area and suspended sediment concentration from Moderate Resolution Imaging Spectroradiometer (MODIS) imagery and field data; (2) ice-sheet melt extent from Special Sensor Microwave/Imager (SSM/I) passive microwave data; and (3) supraglacial lake drainage events from MODIS. Results confirm that the origin of the sediment plume is meltwater release from the ice sheet. Interannual variations in plume area reflect interannual variations in surface melting. Plumes appear almost immediately with seasonal surface-melt onset, provided the estuary is free of landfast sea ice. A seasonal hysteresis between melt extent and plume area suggests late-season exhaustion in sediment supply. Analysis of plume sensitivity to supraglacial events is less conclusive, with 69% of melt pulses and 38% of lake drainage events triggering an increase in plume area. We conclude that remote sensing of sediment plume behavior offers a novel tool for detecting the presence, timing and interannual variability of meltwater release from the ice sheet.
Ice velocity and climate variations for Baltoro Glacier, Pakistan
Authors: Quincey D.J. , Copland L. , Mayer C. , Bishop M. , Luckman A. , Belò M. 
Published: February 2010

AbstractThe recent dynamic behaviour of Karakoram glaciers is expected to differ from that shown by glaciers in the central and eastern Himalaya because of regional variations in precipitation and temperature trends. However, there are insufficient quantitative data to support or confute such hypotheses. We present velocity data covering the period 1993–2008 for Baltoro Glacier, one of the longest glaciers in the Karakoram. Velocity measurements were made using cross-correlation feature tracking applied to European Remote-sensing Satellite (ERS-1 and -2) and Envisat advanced synthetic aperture radar (ASAR) data, supplemented by differential global positioning system (DGPS) measurements. We find a gradual acceleration of the glacier during the early 2000s, in particular during winter months. Multi-seasonal data reveal a large difference between summer and winter flow characteristics, but only in the upper ablation zone. Summer 2005 was a particularly dynamic period following from the heavy winter snowfall of 2004, indicating the importance of basal meltwater availability for glacier flow. Transverse velocity profiles indicate that Baltoro Glacier undergoes ‘block’ flow across much of the upper ablation zone during the summer, which we interpret as evidence of widespread basal sliding. The DGPS data confirm the rapid increase in flow detected during 2005. Modelled climatic data reveal decreasing summer temperatures and increasing precipitation over the study period, helping to explain the observed dynamic variations and their differences from glaciers elsewhere in the Himalaya.
Towards radiocarbon dating of ice cores
Authors: Sigl M. , Jenk T.M. , Kellerhals T. , Szidat S. , Gäggeler H.W. , Wacker L. , Synal H.-A. , Boutron C. , Barbante C. , Gabrieli J. , Schwikowski M. 
Published: February 2010

AbstractA recently developed dating method for glacier ice, based on the analysis of radiocarbon in carbonaceous aerosol particles, is thoroughly investigated. We discuss the potential of this method to achieve a reliable dating using examples from a mid- and a low-latitude ice core. Two series of samples from Colle Gnifetti (4450 m a.s.l., Swiss Alps) and Nevado Illimani (6300 m a.s.l., Bolivian Andes) demonstrate that the 14C ages deduced from the water-insoluble organic carbon fraction represent the age of the ice. Sample sizes ranged between 7 and 100 μg carbon. For validation we compare our results with those from independent dating. This new method is thought to have major implications for dating non-polar ice cores in the future, as it provides complementary age information for time periods not accessible with common dating techniques.
IL-17 Contributes to Angiogenesis in Rheumatoid Arthritis
Authors: Pickens Sarah R. , Volin Michael V. , Mandelin Arthur M. , Kolls Jay K. , Pope Richard M. , Shahrara Shiva 
Published: February 2010

Abstract
Angiogenesis is an early and a critical event in the pathogenesis of rheumatoid arthritis (RA). Neovascularization is dependent on endothelial cell activation, migration and proliferation, and inhibition of angiogenesis may provide a novel therapeutic approach in RA. In this study, we document a novel role of IL-17 in mediating angiogenesis. Local expression of IL-17 in mouse ankles increases vascularity. We further demonstrate that IL-17 is angiogenic by showing its ability to promote blood vessel growth in Matrigel plugs in vivo. Additionally, IL-17, in concentrations present in the RA joint, induces human lung microvascular endothelial cell (HMVEC) migration mediated through the PI3K/AKT1 pathway. Furthermore, suppression of the PI3K pathway markedly reduces IL-17–induced tube formation. We also show that both IL-17–induced HMVEC chemotaxis and tube formation are mediated primarily through IL-17 receptor C. Neutralization of either IL-17 in RA synovial fluids or IL-17 receptor C on HMVECs significantly reduces the induction of HMVEC migration by RA synovial fluid. Finally, RA synovial fluid immunoneutralized with anti–IL-17 and antivascular endothelial growth factor does not reduce HMVEC migration beyond the effect detected by immunodepleting each factor alone. These observations identify a novel function for IL-17 as an angiogenic mediator in RA, supporting IL-17 as a therapeutic target in RA.