bluuebunny/crossref_metadata_2025_split huggingface dataset:
Golden Section’s Numerical Approximations in Terms of Graphics and Application
Authors: Сафиулина  , Safiulina Yu. , Шмурнов  , Shmurnov V. 
Published: September 2014

Golden proportion’s graphic plotting methods have
been considered. A history related to gradual development of views
on Golden section problem as «law of beauty» is traced. Numerical
ratios most frequently used in the art for approximations related to
division of a line segment in extreme and mean ratio have been
provided. An original scheme for «Golden rectangle» construction
based on application offered by Leonardo da Vinci for the quadrature of circle problem solution has been proposed.
Pediatric Population Reference Value Distributions for Cancer Biomarkers and Covariate-Stratified Reference Intervals in the CALIPER Cohort
Authors: Bevilacqua Victoria , Chan Man Khun , Chen Yunqi , Armbruster David , Schodin Beth , Adeli Khosrow 
Published: September 2014

Abstract

BACKGROUND
Cancer biomarkers are commonly used in pediatrics to monitor cancer progression, recurrence, and prognosis, but pediatric reference value distributions have not been well established for these markers. The Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) sought to develop a pediatric database of covariate-stratified reference value distributions for 11 key circulating tumor markers, including those used in assessment of patients with childhood or adult cancers.

METHODS
Healthy community children from birth to 18 years of age were recruited to participate in the CALIPER project with informed parental consent. We analyzed serum samples from 400–700 children (depending on the analyte in question) on the Abbott Architect ci4100 and established reference intervals for α-fetoprotein (AFP), antithyroglobulin (anti-Tg), human epididymis protein 4 (HE4), cancer antigen 125 (CA125), CA15-3, CA19-9, progastrin-releasing peptide (proGRP), carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and total and free prostate specific antigen (PSA) according to CLSI C28-A3 statistical guidelines.

RESULTS
We observed significant fluctuations in biomarker concentrations by age and/or sex in 10 of 11 biomarkers investigated. Age partitioning was required for CA153, CA125, CA19-9, CEA, SCC, proGRP, total and free PSA, HE4, and AFP, whereas sex partitioning was also required for CA125, CA19-9, and total and free PSA.

CONCLUSIONS
This CALIPER study established a database of childhood reference intervals for 11 tumor biomarkers and revealed dramatic fluctuations in tumor marker concentrations between boys and girls and throughout childhood. In addition, important differences between the adult and pediatric population were observed, further highlighting the need for pediatric-specific reference intervals.
Finite morphisms to projective space and capacity theory
Authors: Chinburg Ted , Moret-Bailly Laurent , Pappas Georgios , Taylor Martin J. 
Published: September 2014

Abstract
We study commutative rings R for which all projective schemes over R have
finite morphisms to a projective space of R. We then use our results to define a new kind of capacity
for adelic subsets of projective flat schemes

X

{{X}}

over global fields. This capacity can be used to generalize the converse part of
the Fekete–Szegő Theorem.
Reengineering classic organic reactions using polymeric tools
Authors: Toy Patrick H. 
Published: September 2014

Abstract
Many of the most widely used reactions in organic synthesis suffer from drawbacks that can hamper their use. For example, the Mitsunobu, Wittig and Appel reactions all result in the formation of a full equivalent of triphenylphosphine oxide, which can be similar in polarity to the desired product, and thus be difficult to remove. Other reactions such as the Suzuki-Miyaura and Mizoroki-Heck reactions require the addition of numerous reagents, ligands and catalysts that can be laborious to separate from the targeted cross-coupled product. This review summarizes our recent work to address these issues by developing polymeric tools designed to simplify product isolation from these transformations.
Novel measures based on the Kolmogorov complexity for use in complex system behavior studies and time series analysis
Authors: Mihailović Dragutin T. , Mimić Gordan , Nikolić-Djorić Emilija , Arsenić Ilija 
Published: September 2014

Abstract
We propose novel metrics based on the Kolmogorov complexity for use in complex system behavior studies and time series analysis. We consider the origins of the Kolmogorov complexity and discuss its physical meaning. To get better insights into the nature of complex systems and time series analysis we introduce three novel measures based on the Kolmogorov complexity: (i) the Kolmogorov complexity spectrum, (ii) the Kolmogorov complexity spectrum highest value and (iii) the overall Kolmogorov complexity. The characteristics of these measures have been tested using a generalized logistic equation. Finally, the proposed measures have been applied to different time series originating from: a model output (the biochemical substance exchange in a multi-cell system), four different geophysical phenomena (dynamics of: river flow, long term precipitation, indoor 222Rn concentration and UV radiation dose) and the economy (stock price dynamics). The results obtained offer deeper insights into the complexity of system dynamics and time series analysis with the proposed complexity measures.
A New High-Pressure Triaxial Apparatus for Inducing and Tracking Hydro-Mechanical Degradation of Clayey Rocks
Authors: Pineda Jubert , Romero Enrique , Alonso Eduardo E. , Pérez Tomás 
Published: September 2014

Abstract
This paper presents the development of a new high-pressure triaxial apparatus specifically prepared for inducing and tracking the degradation of clayey rocks. Total suction—used to induce the hydraulic degradation—is applied with vapor transfer technique by controlling the relative humidity of air in contact with the material. The evolution of the degradation process along different hydro-mechanical stress paths is continuously tracked with bender elements, as well as with air or water permeability measurements on partially saturated or saturated states, respectively. Relevant test results on a low porosity clayey rock (Lilla claystone, Spain) are presented to evaluate the main capabilities of the new equipment. The results bring up the high sensitivity to water of the material, which is evidenced by the important reduction of shear wave velocity induced on first wetting and drying at low confining stress, as well as by the significant increase in the air permeability of the degraded material (around four orders of magnitude larger than the intact material). Test results also showed clear differences in the volume change and shear strength behavior of undisturbed, saturated, and degraded samples, highlighting the relevance of degradation on macroscopic behavioral features.
High-Speed Quenching of High Carbon Steel
Authors: Martínez-Cázares G. M. , Lozano D. E. , Guerrero-Mata M. P. , Colás R. , Totten G. E. 
Published: September 2014

AbstractMedium and high carbon steels are usually quenched in polymer and oil in order to avoid cracking and distortion; however, recent studies have proved that it is possible to minimize cracking using water as a coolant of these steels by promoting extremely high cooling rates. By great agitation and velocity of quenchant, the vapor blanket is reduced or prevented during water quench, allowing uniform hardening of the surface. In this study, the cooling severity of a spray quenching system and a high-speed quenching chamber are studied. Cylindrical samples of AISI 304 stainless steel (20 mm in diameter and 100 mm length) were employed to characterize the cooling severity. Thermal data was acquired through K-type thermocouples placed in the sample at three positions, 1 mm below surface, mid-radius and at center of the specimen, connected to a data acquisition system. High thermal gradients were observed in both systems, being the high-speed chamber the severest cooling. The maximum cooling rate obtained at the surface was 470 and 300°C/s for the high-speed chamber and the spray system, respectively. In addition, 5160 spring steel samples were quenched for short times in both systems; the cooling was interrupted to avoid through transformation and to produce a case-core type microstructure. Different cooling times were used for the interrupted quenching to modify the martensite case thickness. No cracks were observed. Thermal results and microstructures are discussed.
Appraisal of Solution Heat Treatment on Elimination of Hafnium Rich γ–γ′ Eutectic and Prior Particle Boundary Precipitate in a Superalloy Powder
Authors: Oluwasegun K. M. , Olawale J. O. , Adeoye M. O. , Olorunniwo O. E. , Ige O. O. , Atanda P. O. 
Published: September 2014

Abstract
Near-net shape hot isostatic pressing (HIPping) in powder metallurgy (P/M) has been on the increase in the production of superalloys for aero and land based turbine disc applications. A critical challenge related to net-shape HIPping PM is the presence hafnium rich γ–γ′ eutectic in some superalloys powder, which promotes the formation of hafnium oxide. This encourages the formation of prior particle boundary (PPB) precipitates during HIPping, which decreases the bonding strength between powder particles during HIPping and thus becomes the crack initiation and growth sites under loading. Hence, this study aims at dissolving hafnium rich γ–γ′ eutectic in RR1000 superalloy powder and eliminating the PPB precipitates after HIPping by heat treating the powder prior HIPping. As-received powder was heat treated at 900, 1000, 1100, and 1200°C for 2 h, and their microstructure was characterized before the application of pressure for its consolidation. From the outcome of the study, 1200°C was found to be the optimum heat treatment temperature where hafnium rich γ–γ′ eutectic dissolved and where prior particle boundary (PPB) precipitates were eliminated during HIPping for the RR1000 superalloy powder studied.
Vegetable Oils as Quenchants for Steels: Residual Stresses and Dimensional Changes
Authors: Civera C. , Rivolta B. , Simencio-Otero R. L. , Lúcio J. G. , Totten G. E. , Canale L. C. F. 
Published: September 2014

AbstractThe development of non-toxic, biodegradable vegetable oils as alternatives to petroleum derived quenchants and their influence on residual stresses and dimensional changes of AISI 4140 and AISI H13 modified C-ring steel test specimens is discussed. The C-ring test specimens were quenched in 6 different vegetable oil blends based on soybean oil and the results were compared to 2 different commercially available petroleum oil quenchants. Residual stresses were determined by X-ray analysis on cylindrical test specimens after quenching. Some measurements were also performed using the hole-drilling method to confirm the results obtained using X-ray analysis.
An Innovative Approach to Reverse Production Decline in Brown Fields
Authors: Guehria Fawzi M. , Collaku Alban 
Published: September 2014

Abstract
It is known that the vast majority of oil and gas fields in the world are on decline; generally in these fields, the high uncertainties stemming from geological complexities and operational risks do not leave much room for risky and costly interventions or ill-planned reactions to issues such as loss of well productivity, water and/or gas breakthoughs. These fields rather need a much elaborated approach to enhance oil or gas throughput while reducing risks and maintaining minimal operations cost. For that, it is best to opt for a strategy, which articulates around day-to-day management through usage of expertise, adapted technology and long-term planning. This requires an integrated approach where the engineering diagnosis/conceptual/ analysis part is intimately tied to the execution/evaluation and other operational and cost constraints.
This work shows through a case study the value of integration in brown field projects. It highlights the fact that by collaborating as a joint project team, excellent results are achieved in field management but also tangible value is gained by unlocking the true reservoir potential that can be achieved through an optimum use of technology and data integration workflows when applied in junction with operations tasks.
Improved Oil Recovery Potential by Using Emulsion Flooding
Authors: Demikhova I. I. , Likhanova N. V. , Moctezuma A. E. , Hernandez Perez J. R. , Olivares-Xometl O. , Lijanova I. V. 
Published: September 2014

Abstract
The present paper deals with emulsion flooding laboratory experiments in porous media, which were performed to investigate the potential use of emulsions as IOR technologies in brownfields of the Gulf of Mexico. Until now, the method of chemical emulsion injections free of siloxanes or fluorinated compounds to promote the hydrophobization of sandstone rocks to reconfigure the phase flow paths, water and oil, generating changes in the flow patterns after the injection of water in order to improve and increase the oil recovery has not been described in the literature.
Oil-in-water emulsions were used along with a sand pack and a sandstone core. The flooding tests were carried out with Ottawa sand and Berea sandstones, respectively. The diameter size of the 90 % dispersed phase (D90), which was represented by a hydrophobic chemical compound, was lower than 5 μm and characterized by laser diffraction; the continuous phase was water. Initially, the oil was displaced by water injection. At the end of this step, the oil production fell to zero; all the oil inside the pore space was immobile. An emulsion slug was then injected, followed by another cycle of water injection. During this process, the additional oil recovery was higher than 15 %.
An oil-in-water emulsion based on a hydrophobic compound blocked a small, water-full pore and additionally, changed the pore surface wettability from water-wet to oil-wet, which modifies the preferential water routes, increasing the volumetric sweep, changing the residual oil saturation and finally, increasing the oil recovery factor.
The results suggest the possibility of using this novel technology in IOR projects for mature oil fields that feature medium gravity (20 °API) and produce high water cut. In addition, this technology is not affected by water salinity and temperature.
Technologies Based on Hydrocarbon-Base Surfactant Compositions for Improved Efficiency of Oil Recovery
Authors: Sobanova O. B. , Lebedev N. A. 
Published: September 2014

Abstract
The scientists of JSC NIIneftepromchim have been developing the reagents and methods for improved efficiency of oil recovery using the hydrocarbon-base surfactant compositions (HBSC) for a number of years.
Application of the compositions containing surfactants of different types instead of the single surfactant changes the properties of these systems over a wide range and adapts the compositions for different geological and physical conditions of the oil fields.
A number of technologies based on HBSC was developed and successfully applied for enhanced oil recovery. The conducted work proves good prospects for application of these technologies for improved efficiency of oil recovery in the mature oil fields with high water cut of well production.
Geomechanic Model Reconstruction for the Choice of Development Strategy
Authors: Mityaev M. , Belozerov B. , Lukin S. 
Published: September 2014

Abstract
Nowadays there is tendency to involve hard-to-recover reserves. As the consequence it starts to involve low permeable reservoirs with high number of permeable intervals in section. These technics demand to practice the new methods of oil development such as horizontal well drilling with multi hydraulic fracturing.
Relatively high coast of such wells poses much higher requirements on cumulative production of every single well. Further concerning of the problem makes efficient sister of pressure maintenance implementation. On of the most encountered issue is the constant water breakthrough as a consequence of pressure close to formation breakdown pressure, low reservoir properties and the last but not least non-correct organized development system (e.g. horizontal wells orientation in case of stress anisotropy).
According to the hydrodynamics modeling data estimation, the maximum of recovery factor for the oil reservoirs achieved by the elongation the development system in one direction with maximum stress line. Therefore the purpose is the maximum recovery factor achievement by the elongation of hydraulic fractures with the rows of injection wells and rows of production wells, making system with piston-like displacement.
One of the main claims of such systems is clear understanding the maximum stress directions in a every particular formation. In the paper the issue is complicated by strike-slip faults and as a consequence strains. Such a strain is hard to be found by seismic data and the determination of the main stress direction in the case of fields with late stage of development becomes hard. This paper concerns the method of stress direction recovery with the help of 3D seismic and early performed hydraulic fracturing.
Risk Evaluation of Investment Decision During Low Oil Prices
Authors: Kolbikov Sergey , Kolbikova Ekaterina , Sholudko Alexander 
Published: September 2014

Abstract
Profitability of investment projects for oil fields development is dropping drastically in the period of low oil prices especially if production drilling is in progress (so called "green fields"). Decision that is usually made in order to keep a positive annual profit during such period often leads to drilling suspension as the most capital-intensive process. Influence assessment of the investment project indicators in terms of fluctuating oil prices and long period of time has not been extended yet.
The analysis of factors affecting the oil price and its trend building are brought in the paper. The evaluation of the investment project on the production drilling in the low oil price period is performed in two scenarios: high oil price volatility trend and current price. It was shown that in order to avoid loses in short term period the company and the government miss the benefits in the long term perspective. The case study is based on the 2008 economic crises. The methodology of project estimation by using high oil price volatility trend within its range of uncertainty is suggested in the paper.
Application of Mathematical Optimization Techniques for Well Pattern Selection
Authors: Khasanov M. M. , Babin V. M. , Melchaeva O. U. , Ushmaev O. S. , Ciaurri D. Echeverria , Semenikhin A. S. 
Published: September 2014

Abstract
The paper describes an approach to selection of horizontal well placement. Given a field dynamic model we use advanced optimization techniques to select horizontal well length, well placement, well control that improve the field economics (as measured by the net present value, NPV) and increase field recoveries. Well-known problems of using optimization algorithms for field development are: (1) big number of variables, simplest well description assumes 5 variables: position, lateral length, orientation, bottom-hole pressure; (2) computational complexity of hydrodynamic simulation. In order to deal with high dimensionality and computation complexity we propose multi-layer approach. First, we decompose optimal well placement and control task of high dimension into a number of optimization problems of lower dimension: selection of optimal well pattern, local well placement optimization, selection of well control. That allows significantly decrease a number of simulation runs. Second, we use chain of simulators and dynamic models (from analytic models to fine-scale hydrodynamic model). The optimal solution for well placement obtained on simple model is used as input (baseline) solution for more complicated models. Thus we reduce number of complicated model runs.
The proposed approach was implemented in experimental software that automatically optimize horizontal well placement and well control using Eclipse dynamic model. We use this software to optimize FDP of a JSC "Gazprom neft" greenfield. The optimization resulted in significant increase of the field NPV and increase of expected recovery factor: 14% and 1.7% respectively. We estimate that optimization techniques contribution is 9% of NPV and 0.4% of RF.
Gazprom Neft Experience of Bazhenov Suite Development
Authors: Vashkevich Alexey , Strizhnev Kirill , Zhukov Vladislav 
Published: September 2014

Abstract
An approach in Bazhenov formation exploration applied by Gazprom Neft is presented. Projects implemented in the company are pointed on making of a complex system that includes regional studies, geological exploration and pilot operations, learning and adaptation of the best world practices and creating own tools and techniques for research and development of Bazhenov formation. Major mining and service companies, science-research institutes are participating in these projects.
By this time multifunctional group of specialists deduced criterions of oil and gas extraction availability, and the most attractive zones ("sweet spots") of Bazhenov formation spreading were selected. On the base of deduced criterions presumptions of Bazhenov formation productivity were gathered. Examining of these presumptions and more detailed exploration of the researched object and approbation of techniques and technologies of oil extraction are being made by geological exploratory and pilot projects in the current licensed spots of the company. The first results of these works showed availability of development of Bazhenov formation in Western Siberia.
Prospects of Shale Oil Bazhenov Formation in the South-East of Western Siberia
Authors: Goncharov I. V. , Samoilenko V. V. , Oblasov N. V. 
Published: September 2014

Abstract
South-east of Western Siberia (Tomsk Region) faces good prospects for developing shale oils from Bazhenov formation. Ample preconditions are available there: high content of organic matter of excellent oil-generating quality in Bazhenov formation rocks and main oil formation stage of primary rocks. However, drilling success appreciably depends on the correct choice of the well spud-in place.
Regional geochemical investigations of Bazhenov formation and of Bazhenov genetic type of oils may considerably confine the area of search by choosing the most promising areas for detecting shale oil deposit.
Recent investigations permitted to identify a regional pattern of changes in Bazhenov formation rocks catagenesis and to grade the prospective regional oil-bearing capacity associated with hydrocarbon generation by Bazhenov formation rocks. Identification of regularities in expansion of Bazhenov - type oils as well as comparison between the maturity of oils and the maturity of organic matter of Bazhenov formation rocks permitted to mark out areas that are promising for the formation of both oil deposit in traditional oil reservoirs and of shale oil deposit.