bluuebunny/crossref_metadata_2025_split huggingface dataset:
Utilization of Surface Drilling Data for Estimation of Sediment Properties in Scientific Drilling of Tohoku Earthquake Zone
Authors: Inoue Tomoya , Katsui Tokihiro , Ujiie Kohtaro , Ishiwata Junya 
Published: October 2015

Japan Agency for Marine-Earth Science and Technology (JAMSTEC) operates the scientific deep-sea drilling vessel Chikyu, which undertook the drilling project under Japan Trench Fast Drilling Program (JFAST) to determine the mechanism of the catastrophic Tohoku Earthquake and the resulting huge tsunami. As targeted drilling sites were located about 1,000 m below the seafloor, at water depths of 7,000 m, JFAST was a challenging deep riserless drilling.
Drilling operation can also provide information on the properties of the drilling layer. This is important as a main aim of the scientific drilling is to obtain core samples from sediment layers under the seabed for evaluating sediment properties. Even a rough estimate of sediment properties could potentially provide an important notice for conducting coring operations.
Thus, we attempted to estimate properties of sediment layers using surface drilling data, such as drilling torque acquired from JFAST, and compare with properties of the core samples. As shear stress of sediment is a key parameter, it was estimated from surface drilling data. It was then compared with shear stress data determined from laboratory tests using core samples, and data from temperature sensors set in borehole.
Stability of Artificial Subaqueous Slopes in Sandy Soils Under Wave Loads
Authors: Bubel Julian , Pick Marc-André , Grabe Jürgen 
Published: October 2015

Shallow foundation structures in marine environments can rarely be placed on top of the sea floor. Weak soils usually need to be excavated to place the structure on more stable ground. Steep but stable slopes of the resulting pit meet both economic and ecologic aims as they minimise material movement and sediment disturbance. This paper focuses changes of geometry of submarine slopes in non-cohesive soils (erosion, sedimentation, breach failure, liquefaction failure) due to surface waves.
After Terzaghi the angle between slope and the horizontal of the ground surface of cohesionless soil is at most equal to the critical state friction angle, as obviously true for dry soil. However, it can be observed that natural submarine slopes of sandy soils are always mildly sloped. During the construction of artificial submarine pits under offshore conditions it should be considered that the long-term slope-inclination is less than onshore due to hydrodynamic actions (e. g. flow, waves, earthquakes). Large surface waves cause excess pore water pressures within the soil body, leading to a reduction of effective stresses and in case of submarine slopes to changes of the slope geometry depending on wave length L, wave height H, water depth h and soil properties (permeability k, relative density Dr).
During our preliminary work we investigated such processes based on the coupling of linear wave theory and linear quasistatic consolidation theory (e.g. [1]). With the help of numerical modelling we solved corresponding equations considering also materially nonlinear consolidation. However, deformations were always limited by used Lagrangian-FEM. Recent developments at our Institute enable the use of an Eulerian-FEM approach with an u-p-Formulation for fully saturated soil [2]. This allows larger deformations of the subaqueous slope to be numerically investigated.
Forced Oscillation Model Tests for Determination of Hydrodynamic Coefficients of Large Subsea Blowout Preventers
Authors: Arino Xavier , de Wilde Jaap , Russo Massimiliano , Grytøyr Guttorm , Tognarelli Michael 
Published: October 2015

Large scale model tests have been conducted in a towing tank facility for the determination of the hydrodynamic coefficients of subsea blowout preventers. A subsea blowout preventer (BOP) is a large, complex device 10–15 [m] tall, weighing 200–450 [ton]. The BOP stack consists of two assemblies, the ‘lower marine riser package’ (LMRP) connected to the riser string and the BOP itself, connected to the wellhead. Together they represent a large lumped mass, which directly influences the natural frequencies and vibration modes of the riser system, particularly those of the BOP-wellhead-casing assembly.
Large uncertainties in the estimates of the hydrodynamic coefficients (added mass, lift and drag or damping) result in large uncertainties in the fatigue damage predictions of the riser and wellhead system. The trend toward larger and heavier BOPs, which could place BOP-wellhead-casing oscillation frequencies in the range of wave frequencies, has motivated Statoil and BP to start a new research project on this subject. The project involves a large scale model test for experimental determination of hydrodynamic coefficients.
Two different BOP designs were tested in a towing tank at model scale 1:12. The models weighed about 50 [kg] in air and were about 1.2–1.5 [m] tall. A six-degree-of-freedom oscillator was mounted under the carriage of the towing tank for oscillation of the models in different directions. Static tow tests and forced oscillation tests with and in the absence of steady current were carried out. Keulegan-Carpenter (KC) numbers ranged between 0.2 and 2.0, while the Sarpkaya frequency parameter β was in the range from 4,000 to 50,000. The Reynolds numbers of the static tow tests ranged between 50,000 and 150,000. This paper focuses particularly on tests in the surge direction with and in the absence of a steady current. Results indicate that the hydrodynamic coefficients for BOP stacks are quite different from those of simpler geometries like a circular cylinder. In addition, they provide new insight for analytical modeling of global hydrodynamic forces on BOPs in many configurations and scenarios.
Optimization of RANS Solver Simulation Setup for Propeller Open Water Performance Prediction
Authors: Islam Mohammed , Jahra Fatima , Doucet Michael 
Published: October 2015

Mesh and domain optimization strategies for a RANS solver to accurately estimate the open water propulsive characteristics of fixed pitch propellers are proposed based on examining the effect of different mesh and computation domain parameters. The optimized mesh and domain size parameters were selected using Design of Experiments (DoE) methods enabling simulations to be carried out in a limited memory environment, and in a timely manner; without compromising the accuracy of results. A Reynolds-Averaged Navier Stokes solver is used to predict the propulsive performance of a fixed pitch propeller. The predicted thrust and torque for the propeller were compared to the corresponding measurements.
A total of six meshing parameters were selected that could affect the computational results of propeller open water performance. A two-level fractional factorial design was used to screen out parameters that do not significantly contribute to explaining the dependent parameters: namely simulation time, propeller thrust and propeller torque. A total of 32 simulations were carried out only to find out that the selected six meshing parameters were significant in defining the response parameters. Optimum values of each of the input parameters were obtained for the DOE technique and additional simulations were run with those parameters. The simulation results were validated using open water experimental results of the same propeller.
It was found that with the optimized meshing arrangement, the propeller opens simulation time was reduced by at least a factor of 6 as compared to the generally popular meshing arrangement. Also, the accuracy of propulsive characteristics was improved by up to 50% as compared to published simulation results. The methodologies presented in this paper can be similarly applied to other simulations such as calm water ship resistance, ship propulsion to systematically derive the optimized meshing arrangement for simulations with minimal simulation time and maximum accuracy. This investigation was carried out using STAR-CCM+, a commercial CFD package; however the findings can be applied to any RANS solver.
An Empirical Heave Induced VIV Prediction Model
Authors: Wu Jie , Lie Halvor , Larsen Carl M. , Baarholm Rolf J. 
Published: October 2015

Steel Catenary Risers (SCRs) are widely used in the development of deepwater oil and gas fields due to their advantages of low manufacturing cost, resistance of high temperature and high pressure, etc. The vertical platform heave motions can cause significant vertical oscillations and hence relative fluid velocities close to the sag-bend area of an SCR. Vortex induced vibrations (VIV) can occur subjected to such periodic variation of relative flow speed.
In order to understand the mechanism of heave induced VIV, Statoil has carried out two model tests in the Ocean Basin in Shanghai Jiaotong University in 2012. A straight flexible beam was tested in an oscillatory flow in one of the tests to study the fundamental behaviour of VIV. Heave induced VIV was investigated in the other test, a truncated SCR model was tested with calculated motions at the top end. Recent studies on these experiments have revealed unique features of VIV in an oscillatory flow. The vortex shedding process is more complicated than that of constant flow. One of the reasons for this is that the pipe will interact with the recent shed vortices when it reverses its motion direction, which may amplify the response. VIV response is not only influenced by the reduced velocity, but also Keulegan–Carpenter (KC) number. In addition, different eigen-frequencies of the pipe can be excited and the mode transition is observed due to the variation of the flow speed during one oscillation period.
There is still lack of prediction tools to evaluate heave induced VIV. It can be desirable to modify the present empirical VIV prediction tools by including additional effects from oscillatory flow. In the present paper, the vortex shedding process during one oscillation period is approximated by several time spans with constant flows. VIV response at each time span is considered to be controlled by a representative flow speed. The final response will be the sum of the responses at different time spans. A riser system analysis program is used to determine the relative flow speeds along an SCR due to heave motions. Then, an empirical VIV prediction program is used to calculate VIV response at different time spans over one top motion period. The prediction results from this integrated approach are compared with experimental results.
Lift Installation of a Subsea Oil Storage Tank: A 60,000mT Pendulum
Authors: Velema Jorick , Bokhorst Job 
Published: October 2015

In August 2014 Heerema Marine Contractors (HMC) have successfully installed the Solan Subsea Oil Storage Tank (SOST), using its Semi-Submersible Crane Vessel (SSCV) Thialf. The SOST installation is regarded as unique due to its dimensions, complex hydrodynamics and the utilization of nearly the full crane capacity.
The Solan SOST is a Subsea Oil Storage Tank with a future storage capacity of 48,000 m3 of oil. The SOST has a dimension of 45m × 45m × 25m, a dry weight of 9,500mT and a total submerged mass of 60,000mT including ballast water. It was installed offshore west of the Shetland Islands at a depth of 135m. Prior to installation the SOST was wet-towed to the field. At location the SOST was installed by a dual crane lift sequence, lowering the SOST from 2m freeboard to the seabed. The lowering sequence is characterized by the usage of a compressible air pocket to reduce hookloads during the most critical stage of the installation, the lowering of the SOST through the splash zone.
Prior to the installation ballast and dynamic lift models were generated to understand both the hydrostatics and hydrodynamics of the SOST - SSCV Thialf system throughout the installation. Numerical simulations of the flooding operation were performed to predict all relevant parameters for various scenarios. The lift dynamics were analysed with frequency domain models. Most resonance modes between SSCV Thialf and SOST were found not to be excited due to the differences in natural periods of the hydrodynamic systems and the occurring wave periods.
During installation vital parameters such as ballast volume, compartment fill rates, differential pressure and hookloads were continuously monitored with dedicated measurement systems. The values were compared with the results from the engineering models. As some of the parameters were directly related to each other, the values could be back-calculated and cross-checked, thereby increasing the reliability of the measurements.
Both the understanding of the principle hydrostatics and hydrodynamics of the system as well as the close monitoring of all vital parameters have resulted in a safe and controlled installation of the Solan SOST by the SSCV Thialf; the installation of a 60,000mT dual crane pendulum. This paper describes the hydromechanic engineering work performed by HMC and the SOST offshore installation.
Temporal Changes in Pipeline-Seabed Condition, and Their Effect on Operating Behaviour
Authors: White D. J. , Leckie S. H. F. , Draper S. , Zakarian E. 
Published: October 2015

It is increasingly recognized that the state of the seabed surrounding an on-bottom pipeline may change during the operating life of the pipeline. For seabed sediments that are soft and fine-grained, the strength may vary through episodes of pipeline movement due to consolidation effects. For seabed sediments that are mobile due to waves and currents, the burial state and the adjacent seabed topography may vary due to sediment transport and scour.
These changes in the strength and topography of the surrounding seabed alter the exposure of the pipeline to hydrodynamic loads and ambient cooling, as well as the level of geotechnical support and insulation provided by the seabed.
The design relevance of these changes in seabed condition is amplified by modern design approaches in which the pipeline itself can be tolerably mobile — for example in a dynamic onbottom stability approach or through engineered schemes of global buckling and axial walking.
This paper illustrates the interactions between the geotechnical and sediment transport processes and the resulting global pipeline behaviour. Two interactions are considered: the long-term axial walking behaviour on soft soil, and the long-term insulation and temperature profile on a mobile seabed.
The examples highlight the potential for over or underestimation of various inputs to a pipeline design when these temporal changes in pipe-seabed condition are overlooked. Emerging analysis methods for pipeline-seabed interaction that incorporate these temporal effects can lead to more reliable and cost-effective design.
A pencil beam approach to proton computed tomography
Authors: Rescigno Regina , Bopp Cécile , Rousseau Marc , Brasse David 
Published: October 2015

Purpose:A new approach to proton computed tomography (pCT) is presented. In this approach, protons are not tracked one‐by‐one but a beam of particles is considered instead. The elements of the pCT reconstruction problem (residual energy and path) are redefined on the basis of this new approach. An analytical image reconstruction algorithm applicable to this scenario is also proposed.Methods:The pencil beam (PB) and its propagation in matter were modeled by making use of the generalization of the Fermi–Eyges theory to account for multiple Coulomb scattering (MCS). This model was integrated into the pCT reconstruction problem, allowing the definition of the mean beam path concept similar to the most likely path (MLP) used in the single‐particle approach. A numerical validation of the model was performed. The algorithm of filtered backprojection along MLPs was adapted to the beam‐by‐beam approach. The acquisition of a perfect proton scan was simulated and the data were used to reconstruct images of the relative stopping power of the phantom with the single‐proton and beam‐by‐beam approaches. The resulting images were compared in a qualitative way.Results:The parameters of the modeled PB (mean and spread) were compared to Monte Carlo results in order to validate the model. For a water target, good agreement was found for the mean value of the distributions. As far as the spread is concerned, depth‐dependent discrepancies as large as 2%–3% were found. For a heterogeneous phantom, discrepancies in the distribution spread ranged from 6% to 8%. The image reconstructed with the beam‐by‐beam approach showed a high level of noise compared to the one reconstructed with the classical approach.Conclusions:The PB approach to proton imaging may allow technical challenges imposed by the current proton‐by‐proton method to be overcome. In this framework, an analytical algorithm is proposed. Further work will involve a detailed study of the performances and limitations of this approach in terms of image quality. The paper shows how to account for the MCS in the reconstruction step with this new approach when an analytical reconstruction algorithm is used.
Genome Sequence of
Paenibacillus
sp. Strain FJAT-28004 for the Genome Sequencing Project for Genomic Taxonomy and Phylogenomics of
Bacillus
-Like Bacteria
Authors: Liu Guo-hong , Liu Bo , Wang Jie-ping , Che Jian-Mei , Zhu Yu-Jing , Chen Qian-Qian , Ruan Chuan-Qing 
Published: October 2015

ABSTRACT

Paenibacillus
sp. strain FJAT-28004 is a spore forming and strictly aerobic bacterium. Here, we report the draft 7,479,858-bp genome sequence of
Paenibacillus
sp. FJAT-28004, which will provide useful information for genomic taxonomy and phylogenomics of the genus
Paenibacillus
, as well as for the functional gene mining and application of
Paenibacillus
sp. FJAT-28004.
First Draft Genome Sequence of Salmonella enterica Serovar Gallinarum Strain VTCCBAA614, Isolated from Chicken in India
Authors: Vaid R. K. , Jindal N. , Anand T. , Bera B. C. , Riyesh T. , Virmani N. , Barua S. , Gupta Renu , Mahajan N. K. , Joshi C. G. , Singh R. K. 
Published: October 2015

ABSTRACT

Salmonella enterica
subsp.
enterica
serovar Gallinarum biovar Gallinarum causes fowl typhoid (FT), which results in huge economic losses to poultry farmers in India. We report the draft genome sequence of
Salmonella
biovar Gallinarum strain VTCCBAA614, isolated from a chicken in an FT affected broiler flock.
High-Quality Draft Genome Sequence of Aneurinibacillus migulanus ATCC 9999
T
(DSM 2895), a Gramicidin S-Producing Bacterium Isolated from Garden Soil
Authors: Wang Jie-ping , Liu Bo , Liu Guo-hong , Ge Ci-bin , Xiao Rong-feng , Zheng Xue-fang , Shi Huai 
Published: October 2015

ABSTRACT

Aneurinibacillus migulanus
ATCC 9999
T
(DSM 2895) is a Gram-positive, round-spore-forming, and gramicidin S-producing bacterium. Here, we report the 6.35-Mb high-quality draft genome sequence of
A. migulanus
ATCC 9999
T
, which will provide useful information for the genomic taxonomy and phylogenomics of
Bacillus
-like bacteria.
Draft Genome Sequence of Bacillus murimartini LMG 21005
T
, an Alkalitolerant Bacterium Isolated from a Church Wall Mural in Germany
Authors: Wang Jie-ping , Liu Bo , Liu Guo-hong , Xiao Rong-feng , Zheng Xue-fang , Shi Huai , Ge Ci-bin 
Published: October 2015

ABSTRACT

Bacillus murimartini
LMG 21005
T
is a Gram-positive, spore-forming, and alkalitolerant bacterium isolated from a church wall mural. Here, we report the 4.17-Mb genome sequence of
B. murimartini
LMG 21005
T
, which will accelerate the application of this alkalitolerant bacterium and provide useful information for genomic taxonomy and phylogenomics of
Bacillus
-like bacteria.
Draft Genome Sequence of Cellulolytic and Xylanolytic
Paenibacillus
sp. A59, Isolated from Decaying Forest Soil from Patagonia, Argentina
Authors: Ghio Silvina , Martinez Cáceres Alfredo I. , Talia Paola , Grasso Daniel H. , Campos Eleonora 
Published: October 2015

ABSTRACT

Paenibacillus
sp. A59 was isolated from decaying forest soil in Argentina and characterized as a xylanolytic strain. We report the draft genome sequence of this isolate, with an estimated genome size of 7 Mb which harbor 6,424 coding sequences. Genes coding for hydrolytic enzymes involved in lignocellulose deconstruction were predicted.
Draft Genome Sequence of Streptomyces fradiae olg1-1, a Strain Resistant to Nitrone-Oligomycin
Authors: Vatlin Aleksey A. , Bekker Olga B. , Lysenkova Ludmila N. , Danilenko Valery N. 
Published: October 2015

ABSTRACT

We report a draft genome sequence of
Streptomyces fradiae
olg1-1, a mutant strain derived from the model object
S. fradiae
ATCC 19609, which is resistant to nitrone-oligomycin and has a mutation in the DNA-binding domain of a transcriptional regulator PadR.
Draft Genome Sequence of Pasteurella multocida Isolate P1062, Isolated from Bovine Respiratory Disease
Authors: Abrahante Juan E. , Hunter Samuel S. , Maheswaran Samuel K. , Hauglund Melissa J. , Tatum Fred M. , Briggs Robert E. 
Published: October 2015

ABSTRACT

Here, we report the draft genome of
Pasteurella multocida
isolate P1062 recovered from pneumonic bovine lung in the United States in 1959.
Genome Sequences of Multidrug-Resistant Salmonella enterica Serovar Paratyphi B (dT+) and Heidelberg Strains from the Colombian Poultry Chain
Authors: Donado-Godoy Pilar , Bernal Johan F. , Rodríguez Fernando , Gomez Yolanda , Agarwala Richa , Landsman David , Mariño-Ramírez Leonardo 
Published: October 2015

ABSTRACT

Salmonella enterica
is a pathogen of significant public health importance that is frequently associated with foodborne illness. We report the whole-genome sequences of four multidrug-resistant
Salmonella enterica
serovar Paratyphi B and Heidelberg strains, isolated from the Colombian poultry chain. The isolates contain a variety of antimicrobial resistance genes for aminoglycosides, β-lactams, fluoroquinolones, sulfonamides, tetracycline, and trimethoprim.
Comparative effectiveness of inhaled corticosteroids for paediatric asthma: protocol for a systematic review and Bayesian network meta-analysis
Authors: Takeuchi Masato , Kano Hirotsugu , Takahashi Kenzo , Iwata Tsutomu 
Published: October 2015

IntroductionUse of inhaled corticosteroid (ICS) is the mainstream maintenance therapy for paediatric asthma. Several forms of ICS are available, but the relative effectiveness among ICS has not been well investigated in published, randomised, controlled trials. The paucity of direct comparisons between ICS may have resulted in insufficient estimation in former systematic reviews/meta-analyses. To supplement the information on the comparative effectiveness of ICS for paediatric asthma, we plan to conduct a network meta-analysis that will enable summary of direct and indirect evidence.Methods and analysisWe will retrieve randomised, controlled trials that examined the effectiveness of ICS for paediatric asthma from the PubMed and Cochrane Central Register of Controlled Trials. After one author scans the title and abstract for eligible studies, two authors will independently review study data and assess the quality of the study. Studies of children (≤18 years old) with chronic asthma or recurrent wheezing episodes will be included if they used ICS for ≥4 weeks. We will define a priori core outcomes and supplemental outcomes of paediatric asthma, including exacerbation, healthcare use and pulmonary function. Studies reporting a minimum of one core outcome will be entered into the systematic review. After the systematic review is performed, extracted data of relevant studies will be synthesised in the Bayesian framework using a random-effects model.Ethics and disseminationThe results will be disseminated through peer-reviewed publications and conference presentations.Protocol registration numberUMIN (000016724) and PROSPERO (CRD42015025889).