bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of Risk Analysis in Design: Safety Aspects Related to the Design and Operation of a FPSO
Authors: Tronstad Lars 
Published: March 2009

Abstract
There are many safety issues related to building and operating a Floating Production, Storage and Offloading unit (FPSO). The paper presents how risk assessments and risk analyses tools were actively used in the design of the Asgard FPSO on the Norwegian Continental Shelf.
The paper covers:
– risk management issues – risk analyses as design tools – risk factors and elements related to design – safety issues related to operation – experience from 10 years of operation
The presentation is general in nature, but the Asgard FPSO is used as the main example. The paper reviews the most relevant and important issues related to safety of FPSOs, and summarize experiences in relation to what design and operational requirements that should be pursued in order to avoid major accidents.
Technology With High Impact on ROI and Low Impact on HSE
Authors: Schwanitz Brian , Henriques Kristine 
Published: March 2009

Abstract
Traditionally, deviated and horizontal wells have been challenging to service in a cost and time-efficient manner. Conventional technology requires large equipment to be mobilized and many heavy lifts in the offshore environment, sometimes with negative HSE consequences.
New technology on electric wireline has made it possible to access the entire well regardless of deviation and lateral reach. Wireline tractors and new mechanical services can be mobilized in a matter of hours and only require a crew of two people for many applications. Transportation can be done by helicopter to avoid the cost and time of mobilizing a full coiled tubing (CT) spread with bottom hole assembly. Additionally, fuel consumption, emissions and fluid discharges are reduced and heavy lifts are eliminated for the offshore environment.
Mechanical down hole wireline tools have also been developed to manage produced water. When wells produce up to 100% of water, mechanical tools can isolate the water to increase oil recovery. By reducing water entry at the source, the subsequent efforts and costs to address it are reduced along with the environmental risks.
This paper will illustrate how HSE benefits can be achieved through several case histories. One case history will show how time and crew requirements can be reduced when a wireline tractor and milling system were deployed to remove 42 ft of barium sulfate inside two wellbores. The scale was removed from both wells in 12 days – the same time it would have taken a CT unit to mobilize and demobilize offshore. Costs were reduced by 60% and crew requirements were reduced from 23 to 12 people compared which reduced human exposure to risks offshore.
Another case history will illustrate how produced water can be effectively reduced through e-line mechanical services. In an offshore well in Norway, a leak was detected in the tubing, which resulted in 85% water cut. A wireline tractor and stroker were applied to install two straddle packers in order to isolate the water-producing area. Water cut was reduced to 5% and oil production increased 800%.
Navier-Stokes Simulations of Surface Waves Generated by Submarine Landslides: Effect of Slide Geometry and Turbulence
Authors: Basu Debashis , Green Steve , Das Kaushik , Janetzke Ron , Stamatakos John 
Published: March 2009

Abstract
Surface waves generated by submarine landslides are studied using a computational model based on Navier-Stokes equations. The volume of fluid (VOF) method is used to track the free surface and shoreline movements. A Renormalization Group (RNG) turbulence model and Detached Eddy Simulation (DES) multiscale model are used to simulate turbulence dissipation. The submarine landslide is simulated using a sliding mass. The three-dimensional numerical simulations are carried out for a freely falling wedge representing the landslide and subsequent wave generations. Simulation results are compared with the experimental data. Modeled illustrate the effect of slide geometry, computational grid, turbulence model parameters, and slide material density on the predicted wave characteristics and runup/rundown at various locations. Computed results also show the complex three-dimensional flow patterns in terms of the velocity field, shoreline evolution, and free-surface profiles. Predicted numerical results for time histories of free-surface fluctuations and the runup/rundown at various locations are in good agreement with the available experimental data.
Breakthrough Mobile Water Treatment Converts 75% of Fracturing Flowback Fluid to Fresh Water and Lowers CO2 Emissions
Authors: Horn Aaron D. 
Published: March 2009

Abstract
Treating and recycling flowback from a hydraulically fractured gas shale reservoir is vital to the development of several shale plays. The use and disposal of water in emerging shale plays is expensive and a significant public and political concern. A breakthrough in water treatment combines an advanced oxidation process (AOP) using ozone and ultrasonic transducers to oxidize heavy metals, soluble and insoluble organics. When combined with reverse osmosis (RO) in a mobile unit, this process allows for significant volumes of flowback to be returned to the environment as fresh, clean water, thereby significantly reducing truck traffic. The hydraulic fracturing process in the Woodford Shale requires 50,000 to 110,000 barrels of water per well. By treating flowback on location with the AOP/RO process, 75% of the volume treated will become clean water with total dissolved solid levels less than 500 ppm. 25% will be clean, concentrated brine water which can be used in subsequent hydraulic fracturing operations. Newfield Exploration executed a pilot 4Q08 during which flowback was processed on location with an AOP/RO unit. Sample analysis from this pilot will be provided to state and federal agencies as a validation of the technology. The mobile unit processed 100 barrels per hour using 220 kW power generation to provide a fresh water stream and brine stream from flowback. The proper application of the AOP/RO process could reduce the fluid disposal carbon footprint by 50 tons of CO2 per well and transform a large portion of industry water use from consumptive to non-consumptive—as much as 25,000 bbl per well. The AOP/RO process could untangle complex operating environments, reduce operating expense and help the environment.
Management of Change System: Focusing on the Basics for Quality Change Management
Authors: Bracey Jennifer , Smith Kris 
Published: March 2009

Abstract
Marathon Oil Corporation's Upstream Organization implemented a simplified Management of Change (MOC) Standard and Training Program to improve knowledge of all employees regarding the definition of Change, the purpose and scope of an effective Hazard Review, and the process for performing a quality Pre Startup Safety Review.
The MOC/PSSR Standard is being rolled out in 2008 and 2009 to all Upstream organizations in the United States, Europe, and Africa. The Standard includes guidance for the steps of the MOC and PSSR process, as well as defined roles and responsibilities. The standard is being applied at both regulatory OSHA PSM facilities, as well as those under other regulatory regimes such as the UK HSE. The Training Program is being applied at all upstream facilities to ensure that all employees understand the definition of Change, and to ensure understanding and importance of a good quality Hazard Evaluation and Pre Startup Safety Review.
The program is in its early stages at this time. We have seen the following tangible benefits: 1.) Improved understanding of Change, Hazard Evaluation process, and Pre Startup Safety Review process, 2.) Implementation of electronic systems with simplified approaches to encourage face to face team Hazard Evaluations and Pre Startup Safety Reviews and reduce employees answering electronic checklist questions in a silo, 3.) Consistent approach to evaluating High, Moderate, and Low complexity changes, and 4.) Consistent approach applied across upstream organizations with varying levels of operational complexity and resources.
We believe this application of MOC will enhance employees’ understanding of Change and quality Hazard Evaluations and PSSRs, resulting in improved process safety performance. Marathon has committed to apply good Process Safety principles across its upstream assets, and a quality MOC program is viewed as a priority for a strong process safety culture.
Optimization of the energy management in water supply systems
Authors: Vieira F. , Ramos H. M. 
Published: March 2009

Water supply systems frequently present high-energy consumption, which correspond to the major expenses of these systems. Energy costs are a function of real consumption and the daily energy tariff.
This paper presents a model of optimization to guarantee the delivery of enough water to populations, for each day. Although, in order to achieve that, energy for pumping is needed, representing the main cost for the companies that operate the systems. The model, developed in MATLAB®, provides the best solution to take in each time step. Simultaneously the population water consumption must be guaranteed, and the hydraulic system restrictions fulfilled. The definition of optimal pumping schedules allows the reduction of operation and maintenance costs associated with pumping energy, as well as the increase of global hydraulic system efficiency. The rules are subsequently introduced into a hydraulic simulator (EPANET), to verify the system behaviour along the simulation period. In addiction, a water turbine is introduced in one of the system's branches. The economical benefits from the generated energy from the water turbine can not be neglected and the wind complementary turbine for pumping supply provides also significant economical savings.
Nano structure of low crystallinity carbon materials analyzed by using high energy X-ray diffraction
Authors: Oshida Kyoichi , Nakazawa Tatsuo , Osawa Kozo , Endo Morinobu 
Published: March 2009

Abstract
In this study, we tried to characterize a kind of low crystallinity carbon materials. The structure of polyparaphenylene(PPP)-based carbon was analyzed by means of high energy X-ray diffraction using the apparatus of SPring-8. The experimental results revealed the existence of basic structural units (BSU) in the highly disordered materials like PPP-based carbon. It is thought that the PPP-based carbons consist of small turbostratic particles, which have a few piled up poly-aromatic layers. The structure of the PPP-based carbon which seemed to be amorphous was estimated to have hexagonal carbon layers with the size of up to 1 nm. The pores in the PPP-based carbon seem to be clearances formed among the BSUs and amorphous carbon. The pore size of PPP-based carbon was estimated from the result of N2 absorption measurement. The experimental results suggested that the lithium ion charge mechanism in the PPP-based carbon differs from that in graphite.
Chaoticity analysis of the current through pure, hydrogenated and hydrophobically modified PEG-Si thin films under varying relative humidity
Authors: Atak Kaan , Aybar Ozgur , Şahin Gokhan , Hacınlıyan Avadis , Skarlatos Yani 
Published: March 2009

Abstract
Polyethylene Glycol has an irregular current characteristic under constant voltage and slowly varying relative humidity. The current through a thin film of Gamma-isocyanatopropyltriethoxysilane added Polyethylene glycol (PEG-Si), its hydrogenated and hydrophobically modified forms, as a function of increasing relative humidity at equal time steps is analyzed for chaoticity. We suggest that the irregular behavior of current through PEG-Si thin films as a function of increasing relative humidity could best be analyzed for chaoticity using both time series analysis and detrended uctuation analysis; the relative humidity is kept as a slowly varying parameter. The presence of more then one regime is suggested by the calculation of the maximal Lyapunov exponents. Furthermore, the maximal Lyapunov exponent in each of the regimes was positive, thus confirming the presence of low dimensional chaos. DFA also confirms the presence of at least two different regimes, in agreement with the behavior of the maximal Lyapunov exponent in the time series analysis. We also suggest that the irregular behavior of the current through PEG-Si can be reduced by hydrogenating and hydrophobically modifying PEG-Si and the improvement in stability can be confirmed by our study.
A new phototransistor with uni-travelling-carrier and optically gradual coupling properties
Authors: Wang L. , Zhao L. , Pan J. , Zhang W. , Wang H. , Zhu H. , Wang W. 
Published: March 2009

AbstractBased on appropriate combination of different band-gap InGaAsP, a new edge-coupled two-terminal double heterojunction phototransistor (ECTT-DHPT) was designed and fabricated, which is double heterojunction, free-aluminium, and works under uni-travelling-carrier mode and optically gradual coupling mode. This device is fully compatible with monolithic micro-wave integrated circuits (MMIC) and heterojunction bipolar transistor (HBT) in material and process. The DC characteristics reveal that the new ECTT-DHPT can perform good optoelectronic mix operation and linear amplification operation by optically biased at two appropriate value respectively. Responsivity of more than 52 A/W and dark current of 70 nA (when VEC = 1 V) were obtained.
Influence of quantum dots shape approximation on size reconstructed from atomic force microscopy measurements
Authors: Piotrowski T. , Sikorski S. 
Published: March 2009

AbstractIn this work we discuss the influence of the atomic force microscopy (AFM) probe tip geometry and the object — quantum dot form on the quantum dots dimension in the growth plane reconstructed from the AFM measurements. It is shown that ignoring the geometry of the probe tip and the quantum dot leads to significant differences between dimensions obtained from the AFM measurements and the real dimensions. Inaccuracies in QD size determination of the nano-objects from AFM measurements are defined.
Structure optimisation of modern GaAs-based InGaAs/GaAs quantum-dot VCSELs for optical fibre communication
Authors: Piskorski Ł. , Wasiak M. , Sarzała R. , Nakwaski W. 
Published: March 2009

AbstractRoom-temperature (RT) continuous-wave (CW) performance of modern 1300-nm oxide-confined In(Ga)As/GaAs quantum-dot (QD) vertical-cavity surface-emitting diode lasers (VCSELs) taking advantage of many QD sheets is investigated using our comprehensive self-consistent simulation model to suggest their optimal design. Obviously, quantum dots should be as uniform as possible and as dense as possible to ensure high enough optical gain. Besides, our simulation reveals that efficient and uniform current injection into VCSEL active regions necessary to enhance excitation of the desired fundamental LP01 mode is accomplished in the VCSEL configuration with the broad-area bottom contact and the ring upper one as well as with the oxide aperture localized within the first period of the upper p-type DBR. The doping of the DBR mirrors is chosen as a compromise between their high enough electrical conductivity and low enough free-carrier absorption. The oxide aperture is additionally introducing the radial optical waveguiding. Moreover, our analysis has been concluded that VCSEL active regions should be composed of at least 9 QD sheets to acquire efficient RT CW operation. Furthermore, rather longer optical cavities are recommended in this case because localization of QD sheets should be adjusted to the anti-node positions of the optical cavity standing wave.
Nearly-analogue blazed phase grating using high birefringence liquid crystal
Authors: Bennis N. , Geday M. , Quintana X. , Cerrolaza B. , Medialdea D. , Spadło A. , Dąbrowski R. , Otón J. 
Published: March 2009

AbstractDiffraction of liquid crystal gratings has been thoroughly studied for many applications such as diffraction optics, optical processing, and spectral analysis. In pure optical processing one varies the direction of propagation of light beam without any mechanical adjustment. In this work we propose a beam steering device using highly birefringent liquid crystal material. Using a highly birefringent material one can reduce the LC layer thickness needed to achieve 2π of phase modulation and thus reduce the fringing effect caused by deformation of the electric field at the edge of the pixel. Here, we present 1.5-µm thick, high-resolution diffraction grating with non-detectable fringing.
Light propagation in highly birefringent photonic liquid crystal fibers
Authors: Ertman S. , Czapla A. , Woliński T. , Nasiłowski T. , Thienpont H. , Nowinowski-Kruszelnicki E. , Dąbrowski R. 
Published: March 2009

AbstractPhotonic liquid crystal fibers have already been demonstrated as a promising perspective for creation of new classes of dynamically tunable optical fiber devices. By combining different geometries of photonic crystal fibers with a variety of different liquid crystals it is possible to obtain a new generation of fibers with dynamically tunable properties, e.g., transmission spectra, attenuation or dispersion.In this paper, tunable birefringence in a commercially available highly birefringent Blazephotonics PM-1550-01 photonic crystal fiber selectively filled with a low birefringence liquid crystal has been experimentally demonstrated. Theses experimental results have been compared with simulations based on the multipole method.
Investigations of dynamic photorefractivity regime by optical polarizing microscopy
Authors: Agashkov A. , Kovalev A. , Parka J. 
Published: March 2009

AbstractWe present a technique, based on optical polarizing microscopy, and results of direct observation of the optical interference field effect on the transient domains excited by ac electric field in a nematic planar cell with photosensitive aligning layers. The light source used in a microscope operated in DC mode as well as in triggered pulse one. Obtained microscopic snapshots of transient domain structure confirmed our assumption of the transient domains reordering (trapping) by the low intensity optical interference field.
Characteristics of electrical properties of wide temperature range TGB phases in liquid crystal dimers
Authors: Dhar R. , Pandey M. , Pandey V. , Pandey A. , Das I. , Achalkumar A. , Yelamaggad C. 
Published: March 2009

Abstract4-n-decyloxy-4′-(cholesteryloxycarbonyl-1-butyloxy) chalcone and its two successive homologous are optically active dimeric compound derived from cholesterol. They possess wide temperature ranges of two twist grain boundary (TGB) phases namely TGBA and TGBC*. Comprehensive dielectric studies have been carried out for these compounds in the frequency range of 1 Hz to 10 MHz for different conditions of molecular anchoring. Various electrical parameter viz. dielectric permittivity, dielectric anisotropy, dc conductivity, and activation energy have been determined for these two TGB phases. Weak relaxation processes have been detected under planar anchoring of molecules in the TGBA and TGBC* phases presumably due to amplitude (soft mode) and phase (Goldstone mode) fluctuations.
Biology and Predation of <i>Stethorus punctillum</i> Weise (Coleoptera: Coccinellidae) feeding on <i>Tetranychus urticae</i> Koch
Authors: Biswas GC , Islam W , Haque MM 
Published: March 2009

The duration of hatching, larval instars and pupal stages of Stethorus punctillum feeding on two-spotted spider mite, Tetranychus urticae were investigated in different seasons under laboratory conditions. The highest values of different developmental stages were obtained during winter. Higher temperature significantly reduced the duration of different developmental stages. No significant effect of relative humidity was exerted on the development stages of S. punctillum. The predation rate of fourth instar larva of S. punctillum was the highest whereas the first instar larva consumed the lowest number of prey. The fourth instar larva of the predator consumed 135.8 eggs, 126.4 larvae, 96.6 nymphs and 72.8 adults per day separately. But the first instar consumed 41.6 eggs, 36.2 larvae, 26.8 nymphs and 16.8 adults during the same period. Keywords: Developmental durations, predation, Tetranychus urticae, Stethorus punctillum Â doi: 10.3329/jbs.v15i0.2196 J. bio-sci. 15: 1-5, 2007
Effect of Temperature on the Predator, <Xylocoris flavipes</i> (Reuter) (Hemiptera: Anthocordiae) Feeding on <i>Cryptolestes pusillus</i> (Schon.) (Coleoptera: Cucujidae)
Authors: Rahman MM , Islam W , Ahmed KN 
Published: March 2009

Xylocoris flavipes (Reuter) is one of the dominant predators of many stored product insect pest including Cryptolestes pusillus. The influence of temperature on predator development, survival and some selected life history parameters was determined. Eggs laid/female (27.27Â±2.52) and egg hatching rate (%) (88.25Â±2.19) were highest at 30Â°C and lowest at 20Â°C (5.43Â±1.19 and 30.79Â±4.63%) respectively but no eggs laid at 15Â°C. Mortality among immature stages (%) was highest (51.71Â±1.48) at 35Â°C and lowest (24.25cÂ±1.14) at 25Â°C. Developmental times decreasing with the increasing of temperature. Maximum numbers of progeny/female/day (3.55Â±0.76) were produced at 25Â°C and minimum (0.83Â±0.04) were at 20Â°C.The sex ratios (% female) of X. flavipes were 47.04, 56.68, 51.66 and 50.07 for 20, 25, 30 and 35Â°C respectively. Survivorship of ovipositing females was highest at 25Â°C but lowest at 35Â°C respectively. Key words: Xylocoris flavipes, Cryptolestes pusillus, life history, temperature, developmental time Â doi: 10.3329/jbs.v15i0.2201 J. bio-sci. 15: 41-46, 2007
Shelf Life Extension of Banana (<i>Musa sapientum</i>) by Gamma Radiation
Authors: Zaman W , Paul D , Alam K , Ibrahim M , Hassan Parvez 
Published: March 2009

The effect of gamma radiation on the shelf life extension of Bananas was studied. Bananas were treated with three gamma radiation doses of 0.30k Gy; 0.40k Gy and 0.50k Gy for 5 mins respectively and stored in a dry place under room conditions (25Â±2Â°C/ 80Â± 5% RH). The physical conditions of the radiation treated and control bananas were observed at every 2 days interval for their organoleptic properties till spoilage. The control bananas ripened within 6 days while the gamma irradiated bananas ripened within 26 days, indicating that the shelf life of banana was extended by 20 days thereby delaying banana ripening. The nutrient contents as well as some important physico-chemical parameters of the irradiated Bananas and the control Bananas were analyzed quantitatively at an interval of 2-4 days throughout the experimental period. A minor decrease in the ascorbic acid content was the only adverse effects observed in irradiated bananas and no other major changes occured in nutritional and organoleptic qualities and the chemical constituents of banana is maintained. A taste-testing panel of 16 panelists determined the acceptability of the fruit. The scores given by the panelists were statistically analyzed and the treated bananas were found to be acceptable up to 26 days at room temperature whereas in the case of control the fruits were spoiled within 6 days. Thus, radiation can be used for the shelf life extension of Bananas and is not harmful to health. Â Key words: Banana, gamma-irradiation, shelf life extension. Â doi: 10.3329/jbs.v15i0.2202 J. bio-sci. 15: 47-53, 2007