bluuebunny/crossref_metadata_2025_split huggingface dataset:
Slim Intelligent Completions Technology Optimize Production in Maximum Contact, Expandable Liner and Quad Laterals Complex Wells
Authors: Shafiq Muhammad , Ali Athar , Al-Haj Haider , Obaidi Ibrahim , Qazi Muhammad Qasim , Kamal S. M. Mansoor 
Published: August 2008

Abstract
This paper describes an innovative completion solutions with reservoir monitoring and control completion technologies that allows commingled oil production from multi-laterals wells in Shaybah inside expandable liner. Slim intelligent completions technology has been successfully installed in Shaybah field, operated by Saudi Aramco. Included in the description are equipment selection, design and development details, installation procedures, and "lessons learned" after installation of the fully hydraulic tubing-retrievable advance completion system with digital permanent down hole monitoring system. Intelligent completions allows individual lateral testing, allocation of production rates to optimize each lateral contribution and the overall commingled well rate. Along with real time monitoring, sustainability of well rate will be extended by timely reacting to any changes to reservoir and well conditions.
Using variable positions flow control valve, early water breakthrough can be delayed to increase recovery factor. Monitoring the flowing pressure in real time allows producing the well at optimum rate; i.e., above bubble point pressure. Ultimately, intelligent completions will limit the water handling at the surface, minimize future intervention and concurrently increase the recovery factor for MRC (Maximum Reservoir Contact) wells.
Cementing High Pressure Formations in the Kingdom of Saudi Arabia
Authors: Berg S. , Noor S. , Barnett N. , Al Yami H. E. , Nawaz K. 
Published: August 2008

Abstract
Cementing deep high pressure and high temperature (HPHT) gas wells has always been a challenge. Conventional heavy weight cement systems which have been used in the past have often had to sacrifice the set cement mechanical properties such as compressive strength, permeability, and porosity, to provide a slurry design which is stable, mixable and pumpable. Utilizing an optimized High Density High Performance Slurry (HDHPS) the challenge has been successfully overcome for the HPHT in the Ghawar Reservoir in the Kingdom Of Saudi Arabia. The concept of the particle size distribution was applied to provide a cost effective solution to cementing of these HPHT wells.
The packing volume fraction was optimized for the cement blend. As a result, the slurry properties become a function of the dry blend instead of the additives in the slurry system. Particle Size Distribution optimizes both slurry and set cement properties simultaneously. The permeability and porosity of the set cement are reduced due to improved particle packing of the system. In addition, the rheological properties are improved which alleviates settling problems commonly encountered with conventional high density cement slurries.
Extensive lab testing and yard trial prior to field application demonstrated the superior performance of these slurries over conventional cements in both the liquid phase and when set.
To date, four 9 5/8" casing strings and two 7" Liners have been isolated in the Jilh formation using HDHPS technology, with cement weights above 20 ppg (2400 kg/m3). Details of the slurry technology are presented along with data documenting the jobs performed to date in Kingdom of Saudi Arabia. The system is widely accepted by Saudi Aramco and is the preferred system for critical high pressure cementing.
The Use of StageFrac New Technology to Complete and Stimulate Horizontal Wells: Field Case
Authors: Franco C. , Solares R. , Marri H. , Hussain H. 
Published: August 2008

Abstract
This paper summarizes the results from the deployment of a StageFrac completion and multi-stage acid fracturing treatment in the first field trial conducted in a Saudi Aramco gas producer. The main objective of the field trial was to ascertain the effectiveness of this state-of-the-art technology in properly stimulating long horizontal gas producers and be able to use it to help severely damaged or under-performing wells achieve their maximum potential. The secondary objective was to evaluate the ability to connect the main Khuff-C producing zones through hydraulic fracturing and thus ascertain the viability of this technology as a potential alternative for dual-lateral completions in certain parts of the field.
Drilling problems necessitated the reduction of the total horizontal well from the originally planned 5,000 ft. to a final length of 3,835 ft. Moreover, mechanical problems encountered while setting the StageFrac completion reduced the total horizontal length open to flow to 1,440 ft. only, leaving 2,394 ft. isolated and unable to flow. Hence, the number of fracture stages originally planned at six had to be reduced to only three, but stimulation operations were implemented trouble-free with a good number of lessons learned that will be applied in future applications of the technology. Nevertheless, the initial performance of the well compares favorably with that of two other non-stimulated horizontal gas producers with better reservoir quality and more reservoir contact, a clear indication of the successful stimulation effect achieved with the job.
This technology offers significant potential to improve the productivity of under-performing horizontal producers and help them achieve their maximum potential.
Computation of Average Well Drainage Pressure for a Parallel Reservoir Simulator
Authors: Middya Usuf , Dogru Ali H. 
Published: August 2008

Abstract
In history matching, simulator computed well pressures are matched against the static well pressures from the field data. In practice, many simulators use pore volume averaged grid block pressures for the perforated cells to calculate the static well pressure. While this approximation may be reasonable for large grid blocks, it certainly is not a good approximation for the smaller grid blocks. When locally refined grids around the well are used, the error becomes significant.
This paper describes a new method where the static well pressure is calculated from the approximate well drainage volume during the simulation. Drainage volume of the well is estimated from the computed fluxes. Static well pressure is then calculated by pore volume average of the dynamic grid block pressures within the drainage volume. The novelty of the method comes from the fact that fluid fluxes are computed at each iteration in a numerical reservoir simulator as part of the simulator computations. Therefore, no extra computations are needed to calculate effective drainage volume. Implementation in a parallel simulator where well blocks may cross the processor domain boundaries are handled by the new algorithm and described in the paper.
New method has been compared against the conventional method and field data. Advantages of the new method are illustrated by examples including a real field simulation.
Cyclic Production Scheme: Innovative Application in Reducing Water Production and Increasing Ultimate Recovery from Mature Areas
Authors: Al-Mutairi Saad , Al-Yousef Hasan , Al-Ajmi Fahad , Al-Hashim Hasan 
Published: August 2008

Abstract
Handling excessive water production is one of the most common challenges in mature oil fields. The world produces almost five barrels of water with each barrel of oil. Cyclic Production Scheme (CPS) was applied as a first field trial in the world in one of mature oil fields in Saudi Aramco to maximize ultimate oil recovery, reduce water production and enhance reservoir pressure.
The results of a conceptual simulation model that was built to assess reservoir performance under the CPS are discussed. Sensitivity cases were carried out to identify the most influential reservoir parameters on CPS. This assessment is to support the understanding and engineering interpretation behind the performeance of the CPS.
Synthesis and structure of a µ‐oxo diiron(III) complex with an N‐pyridylmethyl‐N,N‐bis(4‐methylbenzimidazol‐2‐yl)amine ligand and its catalytic property for hydrocarbon oxidation
Authors: Sun Hongfei , Wang Mei , Li Fei , Li Ping , Zhao Zhenbo , Sun Licheng 
Published: August 2008

AbstractA µ‐oxo diiron(III) complex [{Fe(pbba)Cl}2(µ‐O)]Cl2 (1, pbba = N‐pyridylmethyl‐N,N‐bis(4‐methylbenzimidazol‐2‐yl)amine) bearing multi‐imidazolyl motifs was synthesized and characterized by X‐ray crystallography to closely mimic the structural features of methane monooxygenase. As shown by its X‐ray crystal structure, complex 1 is a centrosymmetric dimer with an FeOFe angle of 180° , and pseudo‐octahedral around each iron(III) center. The catalytic ability of title compound in the oxidation of alkane and alkene is investigated by employing tert‐butylhydroperoxide and m‐chloroperbenzoic acid as oxidants under mild conditions. The catalytic oxidation results showed that radical intermediate dominates the oxidation process. Copyright © 2008 John Wiley & Sons, Ltd.
An optimal effective controller for discrete event systems
Authors: Chen Yi‐Liang , Lin Feng 
Published: August 2008

AbstractAn approach to the online synthesis of an optimal effective controller for discrete event systems is presented. The optimal effective controller can achieve the prescribed (cumulative) effectiveness measure while minimizing the total cost incurred for the execution of events. This approach is constructed over a generalized control framework for automata‐based discrete event systems, which allows event enforcement in addition to the (original) event disablement/enablement as the control mechanism. The optimal effective control policy generated by this approach is proved to be the least restrictive among all the possible optimal effective control policies for the given online expansion tree of the system behavior. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Chaotic synchronization in the presence of disturbances based on an orthogonal function neural network
Authors: Wang Hongwei , Gu Hong 
Published: August 2008

AbstractChaos synchronization problems are addressed in this paper. For chaotic synchronization systems with uncertainties and external disturbances, an orthogonal function neural network is used to achieve the synchronization of chaotic systems. Legendre orthogonal polynomials are selected as the basis functions of the orthogonal function neural network. An adaptive learning law is derived to guarantee that the tracking errors are bounded using Lyapunov stability theory. Simulation results show the efficiency of the proposed scheme. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
A coordinating approach for the solution of discrete linear servo‐mechanism problems with constraints
Authors: Hassan Mohamed F. , Ali Awatef K. 
Published: August 2008

AbstractA discrete‐time linear servo‐mechanism problem with system constraints is considered. An approach is developed to solve such a problem using an idea borrowed from large‐scale systems theory, in which a coordinating variable is introduced and used to satisfy state constraints. Under the assumption that the system is stabilizable and has a feasible solution, it is shown that the proposed procedure leads to the optimal solution while satisfying system constraints. A convergence analysis of the algorithm is undertaken and illustrative examples are provided to show the performance of the proposed algorithm. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Nonlinear Luenberger‐like observers for nonlinear MIMO systems
Authors: Mangsuli Purnaprajna R. , Rao N. J. 
Published: August 2008

AbstractThis paper deals with the design of observers for a class of continuous time nonlinear multi‐input multi‐output systems with nonlinear outputs. Geometric tools are used to transform the original system into an appropriate observer canonical form. Furthermore, a pole placement technique is used to obtain a desired transient response of resulting error dynamics. The observer design is presented for two cases. In both cases, it is shown that the observer gain can be obtained from the solution of a Riccati equation. An illustrative example of state estimation in induction motors is presented to explain the proposed observer design. The performance of the method is also verified by numerical simulations. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Model predictive functional control for processes with unstable poles
Authors: S Igor 
Published: August 2008

AbstractIn this paper the coprime‐factorized model predictive functional control for single‐input single‐output processes with an arbitrary number of unstable poles is presented. The predictive functional control algorithm gives a framework for designing the control for a wide range of processes. The main idea in the case of unstable poles is based on the prediction of the process output based on the coprime‐factorized process model. The robust stability of the proposed control algorithm is also discussed, using the small‐gain theorem, which provides a sufficient condition for stability. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Modeling the interaction between objects and cartoon water
Authors: Yu Jinhui , Liao Jing , Patterson John 
Published: August 2008

AbstractIn this paper, we describe a method for modeling the interaction between objects and the cartoon water which does not involve physics simulations. Our method involves the definition of flow path lines in the presence of obstacles, modeling of different types of water forms, and combinations of them in space and time. There are several notable features with our method: easy setting with little user intervention, modeling of complex water forms that represent more energetic water behavior than has been encompassed by semi‐automatic means so far, and the adaptive change of animated water forms to the variation of obstacle object in number, size, and shape in the water path. A number of formulae for managing shape and time variance in these animations are given. We tested our method with both still and moving objects that have different shape and size in the water and relevant examples are given in the paper. Copyright © 2008 John Wiley & Sons, Ltd.
Multi‐resolution parametric synthesis of manipulative dynamic textures
Authors: Xu Leilei , Sun Hanqiu , Wang Lifeng 
Published: August 2008

AbstractDynamic textures are composed of spatially multi‐scale and temporally coherent visual signals. In this paper, we propose a novel approach for multi‐resolution parametric synthesis (MPS) of manipulative dynamic textures, including learning, analysis, and motion manipulation of layered feature spaces. The proposed approach separates the motions into different scales or frequencies, and the dynamic feature spaces are analyzed in modeling and then mapped to a global coordinate system to expose the multi‐scale structures. Our approach emphasizes the importance of fine‐scale data appearing more informative, while coarse signals are less focused. The synthesized dynamic textures using our MPS approach are strongly enhanced in dynamic appearance than the single‐scale LDS model, and also flexible in manipulating the decomposed feature spaces for creating different dynamic textures of the real world. Our experimental results showed the more faithful synthesized dynamic textures from input short videos, and their manipulative controls by simple editing of feature space basis, not only the whole video data. Copyright © 2008 John Wiley & Sons, Ltd.
From Single‐Molecule Precursors to Coupled Ag2S/TiO2 Nanocomposites
Authors: Neves Márcia C. , Monteiro Olinda C. , Hempelmann Rolf , Silva Artur M. S. , Trindade Tito 
Published: August 2008

AbstractA single‐source approach using mild temperatures was applied to prepare morphological well‐defined and coupled TiO2/metal–sulfide nanocomposites. Metal N‐alkyldithiocarbamates were used as the precursors to the metal–sulfide nanophases and, in particular, Ag2S nanostructures were investigated in more detail. These were observed as nano‐islands at the surface of TiO2 (anatase) particles, which were used as substrates. To explain the formation of these nanocomposite particulates, a tentative mechanism has been proposed which involves the controlled release of sulfide ions from an intermediate coordination compound. Because the growth of the metal sulfide can be controlled at the surface of a photoactive substrate, we anticipate the potential of this synthetic method to chemical design reasonable amounts of semiconductor‐sensitized TiO2, such as Ag2S/TiO2 nanocomposites. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
New Musk Odorants: (3E)‐4‐(2′‐Alkyl‐5′,5′‐dimethylcyclopent‐1′‐enyl)but‐3‐en‐2‐ones and (3E)‐1‐Acetyl‐3‐alkylidene‐4,4‐dimethylcyclohexenes
Authors: Kraft Philip , Popaj Kasim 
Published: August 2008

AbstractFour new representatives, 18, 23, 29, and 32, of the young family of dienone musks were synthesized by two general routes. The first five‐step synthetic route leading to (3E)‐4‐(2′‐alkyl‐5′,5′‐dimethylcyclopent‐1′‐enyl)but‐3‐en‐2‐onescommenced with the enolate alkylation of 2,2‐dimethylcyclopentanone (13), either directly with an alkyl halide or through the Reetz tert‐alkylation. Subsequent cerium(III)‐mediated butynol Grignard reaction, dehydration with sulfuric acid, (E)‐selective partial reduction of the triple bond with lithium aluminum hydride, and concluding pyridinium chlorochromate oxidation complemented this route. The second four‐step route leading to (3E)‐1‐acetyl‐3‐alkylidene‐4,4‐dimethylcycloalk‐1‐enes commenced with the Woods–Grignard modification on the vinylogous ester 3‐ethoxycyclohex‐2‐enone (24) employing ethylmagnesium bromide. The product 25 was then gem‐6,6‐dimethylated by its lithium enolate to provide 26, which was subjected to a Schlosser–Wittig reaction to introduce the 3‐alkylidene substituent. Dirhodium(II) caprolactamate‐catalyzed allylic oxidation with tert‐butyl hydroperoxide completed the second general synthetic scheme. The four target compounds, 18, 23, 29, and 32, were designed as diseco derivatives of a carotol lead, and they all constitute musk odorants with floral‐fruity side notes. A tert‐butyl group at the C‐6 position of the (E)‐hexa‐3,5‐dien‐2‐one skeleton was found to intensify the musk odor, and (E)‐4‐(2′‐tert‐butyl‐5′,5′‐dimethylcyclopent‐1′‐enyl)but‐3‐en‐2‐one (23) was found the most intense and interesting odorant of the series, with a very uncommon undertone of beetroot and dried fruits.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
The prevalence of cognitive impairment with no dementia in older people: The seoul study
Authors: Choo Il Han , Lee Dong Young , Lee Jung Hie , Kim Ki Woong , Jhoo Jin Hyeong , Ju Young‐Su , Yoon Jong Choul , Kim Shin Gyeom , Ha Jin , Woo Jong Inn 
Published: August 2008

AbstractObjectiveThis study aimed to estimate prevalence of cognitive impairment with no dementia (CIND) in older people. It was conducted in an urban area of Korea, Seoul, and employed a two‐stage design for case identification.MethodsOverall 643 persons aged 65 years and older participated and 217 persons sampled from the three levels of performance of MMSE underwent a second stage clinical evaluation. CIND was diagnosed when the global Clinical Dementia Rating (CDR) index was 0.5 and the Diagnostic and Statistical Manual of Mental Disorders, 4th edition diagnostic features of dementia were not satisfied. CIND cases without any apparent causes were classified as CIND of unidentified cause (CINDuc).ResultsCIND prevalence ranged from 26.3% in persons aged 65–69 to 46.5% in persons aged 85 years and older. The age‐standardized prevalence for overall CIND was 31.9% and for CINDuc 19.2%. The prevalences of CIND for the three severity grade were 15.8%, 9.7%, and 6.2% for CDR sum of boxes scores of 0.5, 1–1.5, and ≥2, respectively.ConclusionsThe prevalence of CIND in community‐residing elderly is probably higher than previously reported. The results of this study are useful for assessments of present and future demands for healthcare services. Copyright © 2008 John Wiley & Sons, Ltd.
Antihyperlipidemic effect of D‐pinitol on streptozotocin‐induced diabetic wistar rats
Authors: Geethan P. K. M. Anu , Prince P. Stanely Mainzen 
Published: August 2008

AbstractD‐pinitol (3‐O‐methyl‐chiroinositol), an active principle of the traditional antidiabetic plant, Bougainvillea spectabilis, is claimed to exert insulin‐like effects. This study was undertaken to evaluate the effect of D‐pinitol on lipids and lipoproteins in streptozotocin (STZ)‐induced diabetic Wistar rats. Rats were made type II diabetic by single intraperitoneal injection of STZ at a dose of 40 mg/kg body weight. STZ‐induced diabetic rats showed significant (p < 0.05) increase in the levels of blood glucose and total cholesterol, triglycerides, free fatty acids, and phospholipids in serum, liver, kidney, heart, and brain. The levels of low‐density lipoprotein (LDL) and very low‐density lipoprotein (VLDL) cholesterol were significantly increased, and the level of high‐density lipoprotein (HDL) cholesterol was significantly decreased in diabetic rats Oral administration of D‐pinitol to STZ‐induced diabetic rats showed significant (p < 0.05) decrease in the levels of blood glucose and total cholesterol, triglycerides, free fatty acids, and phospholipids in serum, liver, kidney, heart, and brain. The D‐pinitol also lowered significantly (p < 0.05) LDL and VLDL cholesterol levels and increased significantly (p < 0.05) HDL cholesterol levels in the serum of diabetic rats. Thus, the present study clearly showed the antihyperlipidemic effect of D‐pinitol in STZ‐induced type II diabetic rats. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:220–224, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20218
Analysis of green pit viper (Trimeresurus alborabris) venom protein by LC/MS‐MS
Authors: Soogarun Suphan , Sangvanich Polkit , Chowbumroongkait Montri , Jiemsup Surasak , Wiwanikit Viroj , Pradniwat Paweena , Palasuwan Attakorn , Pawinwongchai Jaturawat , Chanprasert Supanthitra , Moungkote Tusrin 
Published: August 2008

AbstractGreen pit viper venom has major effect on the hematological system having a thrombin‐like effect. Thus, this study is designed to analyze the composition of Trimeresurus albolabris venom by performing gel filtration and LC/MS‐MS. The purified protein was then digested by trypsin, and the tryptic fragments were analyzed by iontrap spectrophotometry. This study found four types of proteins, namely jerdonitin, stejaggregin‐A β chain‐1, stejnobin, and stejnihagin‐A, as the components of T. albolabris venom. All of these toxins played a greater or lesser role in clot formation or otherwise contributed to cross‐reactions in antivenom production. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:225–229, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20232