Optimization Of Well Location And Number Of Production Well

The optimal location of drilling the wells. in the oil and surrounding application has caused a significant economical impact on the reservoir management. The wells location issue in a productive formation is a vital aspect in order to have an effective . field development. However, the determination of the optimal wells location in the specific geographical locations is a challenging matter since it depends on the geological and the fluid properties, reservoir characteristics and as well as on the economic parameters. Hence, reservoir simulation is recognized as one of the most . reliable tools for defining the optimum strategy of production. Nevertheless, using the simulation approach in doing the forecasting bears the risk of uncertainty in the input data. Due to the reservoir inhomogeneity and the uncertainty in the reservoir description, solution to the problem is impossible at the intuitive level. Using the conventional approach to define the number of production wells and its locations is a costly trial and error process as the outcome is fully depends on the ability of the reservoir engineer to understand the reservoir behavior and its operational limits. Thus, an alternative approach in optimizing the well location which is by determining the high productivity zone within the reservoir where the hydrocarbon production is expected to reach the maximum field production. It is performed by evaluating each. of the possible well position at different locations and defining the sensitivity of several reservoir properties which will have the significant impact to the optimum well placement. The. studied was carried out on an actual Malaysia reservoir model which is the Gelama Merah field located in offshore Sabab. By utilizing the Eclipse lOO - A black oil model simulator software, several studies have been made and the predicted values of production were significantly promising. Furthermore, it was found that the. optimal well production duration is a function of well spacing with respect to the number of production well drilled. Apart from that, changing of oil saturation (So) will always contribute to the high impact for the optimal well placement and oil productivity. Hence, the method proposed could be one of the useful tool to assist the progress in the decision making for the field development and strikes towards the optimal and effective hydrocarbon recovery

Tree growth and management in Ugandan agroforestry systems: effects of root pruning on tree growth and crop yield

Tree root pruning is a potential tool for managing below-ground competition when trees and crops are grown together in agroforestry systems. This study investigates its effects on growth and root distribution of Alnus acuminata (HB & K), Casuarina equisetifolia (L), Grevillea robusta (A. Cunn. ex R. Br), Maesopsis eminii (Engl.), and Markhamia lutea (Benth.) K. Schum. and on yield of adjacent crops in sub-humid Uganda. The trees were 3 years old at the commencement of the study, and most species were competing strongly with crops. Tree roots were pruned 41 months after planting by cutting and back-filling a trench to a depth of 0.3 m, at a distance of 0.3 m from the trees, on one side of the tree row. The trench was re-opened and roots re-cut at 50 and 62 months after planting. Effects on tree growth and root distribution were assessed over a 3 year period, and crop yield after the third root pruning at 62 months is reported here. Overall, root pruning had only a slight effect on tree growth: height growth was unaffected and diameter growth was reduced by only 4 %. A substantial amount of root re-growth was observed by 11 months after pruning. Tree species varied in the number and distribution of their roots, and Casuarina and Markhamia had considerably more roots per unit of trunk volume than the other tree species, especially in the surface soil layers. Casuarina and Maesopsis were the most competitive tree species with crops and Grevillea and Markhamia the least. Crop yield data provides strong evidence of the redistribution of root activity following root pruning, so that competition increased on the unpruned side of tree rows. Thus, one-sided root pruning will only be of use to farmers in a few circumstances. Key words: Alnus acuminata, Casuarina equisetifolia, Grevillea robusta, Maesopsis eminii, Markhamia lutea, root distribution, root functio

Multiparameter Moment Matching Model Reduction Approach for Generating Geometrically Parameterized Interconnect Performance Models

In this paper we describe an approach for generating geometrically-parameterized integrated-circuit interconnect models that are efficient enough for use in interconnect synthesis. The model generation approach presented is automatic, and is based on a multi-parameter model-reduction algorithm. The effectiveness of the technique is tested using a multi-line bus example, where both wire spacing and wire width are considered as geometric parameters. Experimental results demonstrate that the generated models accurately predict both delay and cross-talk effects over a wide range of spacing and width variation.Singapore-MIT Alliance (SMA

Viral quasispecies inference from 454 pyrosequencing

10.1186/1471-2105-14-355BMC Bioinformatics141-BBMI

Non-repudiation in an agent-based e-commerce system

Abecos is an agent-based e-commerce system under development at the Nanyang Technological University. It aims to provide a software infrastructure for a large scale, distributed system whereby seller and buyer (software) agents engage in e-commerce activities on behalf of organizations and individuals. A key factor in making this system usable in practice is strict security controls. One aspect of security is the provision of non-repudiation services. As protocols for non-repudiation have focused on the singlemessage non-repudiation, its adaptation to afford non-repudiation in a communication session for two agents in Abecos is inefficient. In this work, we investigate and propose a protocol for enforcing non-repudiation in a session. We compare and show that it is more efficient than simple adaptations of existing protocols. Keywords: Electronic Commerce, Security, Non-Repudiation Protocol 1 Introduction Electronic commerce is an emerging paradigm of business on the fast g..

Predictors of high-cost hospitalization in the treatment of acute coronary syndrome in Asia: findings from EPICOR Asia.

BACKGROUND: The EPICOR Asia (long-tErm follow-uP of antithrombotic management patterns In acute CORonary syndrome patients in Asia) study (NCT01361386) was an observational study of patients hospitalized for acute coronary syndromes (ACS) enrolled in 218 hospitals in eight countries/regions in Asia. This study examined costs, length of stay and the predictors of high costs during an ACS hospitalization. METHODS AND RESULTS: Data for patients hospitalized for an ACS (n = 12,922) were collected on demographics, medical history, event characteristics, socioeconomic and insurance status at discharge. Patients were followed up at 6 weeks' post-hospitalization for an ACS event to assess associated treatment costs from a health sector perspective. Primary outcome was the incurring of costs in the highest quintile by country and index event diagnosis, and identification of associated predictors. Cost data were available for 10,819 patients. Mean length of stay was 10.1 days. The highest-cost countries were China, Singapore, and South Korea. Significant predictors of high-cost care were age, male sex, income, country, prior disease history, hospitalization in 3 months before index event, no dependency before index event, having an invasive procedure, hospital type and length of stay. CONCLUSIONS: Substantial variability exists in healthcare costs for hospitalized ACS patients across Asia. Of concern is the observation that the highest costs were reported in China, given the rapidly increasing numbers of procedures in recent years. TRIAL REGISTRATION: NCT01361386

Stringy Stability of Charged Dilaton Black Holes with Flat Event Horizon

Electrically charged black holes with flat event horizon in anti-de Sitter space have received much attention due to various applications in Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence, from modeling the behavior of quark-gluon plasma to superconductor. Crucial to the physics on the dual field theory is the fact that when embedded in string theory, black holes in the bulk may become vulnerable to instability caused by brane pair-production. Since dilaton arises naturally in the context of string theory, we study the effect of coupling dilaton to Maxwell field on the stability of flat charged AdS black holes. In particular, we study the stability of Gao-Zhang black holes, which are locally asymptotically anti-de Sitter. We find that for dilaton coupling parameter $\alpha$ > 1, flat black holes are stable against brane pair production, however for 0 < $\alpha$ < 1, the black holes eventually become unstable as the amount of electrical charges is increased. Such instability however, behaves somewhat differently from that of flat Reissner-Nordstr\"om black holes. In addition, we prove that the Seiberg-Witten action of charged dilaton AdS black hole of Gao-Zhang type with flat event horizon (at least in 5-dimension) is always logarithmically divergent at infinity for finite values of $\alpha$, and is finite and positive in the case $\alpha$ tends to infinity . We also comment on the robustness of our result for other charged dilaton black holes that are not of Gao-Zhang type.Comment: Fixed some confusions regarding whether part of the discussions concern electrically charged hole or magnetically charged one. No changes to the result

Methylation levels of a novel genetic element, EgNB3 as a candidate biomarker associated with the embryogenic competency of oil palm

The association between DNA methylation status and embryogenic competency in oil palm tissue culture was examined through Representational Difference Analysis (RDA) approach, using methylation-sensitive restriction endonucleases. "Difference Products" (DPs) of RDA derived from palms of similar genetic backgrounds but exhibiting different embryogenesis rates during the regeneration process were isolated. The DPs were sequenced using a pyrosequencing platform. To our knowledge, this is the first study profiling partial HpaII methylation sites in oil palm young leaf tissues which are potentially associated with embryogenic amenability through a genomic subtractive approach. Quantitative real-time PCR analysis demonstrated that the methylation status of a novel fragment, EgNB3, was higher in highly embryogenic leaf explants compared to low embryogenesis rate materials. These differences are likely to be contributed by the 5′-mCCGG-3′ and/or 5′-mCmCGG-3′ methylation patterns. Our data suggest that the differentially methylated site in EgNB3 has potential as a molecular biomarker for the screening of oil palm leaf explants for their embryogenic potentials

Effect of concurrent mitral valve surgery for secondary mitral regurgitation upon mortality after aortic valve replacement or coronary artery bypass surgery

ObjectivesIt is uncertain whether concurrent mitral valve repair or replacement for moderate or greater secondary mitral regurgitation at the time of coronary artery bypass graft or aortic valve replacement surgery improves long-term survival.MethodsPatients undergoing coronary artery bypass graft and/or aortic valve replacement surgery with moderate or greater secondary mitral regurgitation were reviewed. The effect of concurrent mitral valve repair or replacement upon long-term mortality was assessed while accounting for patient and operative characteristics and mitral regurgitation severity.ResultsOf 1,515 patients, 938 underwent coronary artery bypass graft or aortic valve replacement surgery alone and 577 underwent concurrent mitral valve repair or replacement. Concurrent mitral valve repair or replacement did not alter the risk of postoperative mortality for patients with moderate mitral regurgitation (hazard ratio = 0.93; 0.75–1.17) or more-than-moderate mitral regurgitation (hazard ratio = 1.09; 0.74–1.60) in multivariable regression. Patients with more-than-moderate mitral regurgitation undergoing coronary artery bypass graft-only surgery had a survival advantage from concurrent mitral valve repair or replacement in the first two postoperative years (P = 0.028) that did not persist beyond that time. Patients who underwent concurrent mitral valve repair or replacement had a higher rate of later mitral valve operation or reoperation over the five subsequent years (1.9% vs. 0.2%; P = 0.0014) than those who did not.ConclusionsThese observations suggest that mitral valve repair or replacement for more-than-moderate mitral regurgitation at the time of coronary artery bypass grafting may be reasonable in a suitably selected coronary artery bypass graft population but not for aortic valve replacement, with or without coronary artery bypass grafting. Our findings are supportive of 2021 European guidelines that severe secondary mitral regurgitation “should” or be “reasonabl[y]” intervened upon at the time of coronary artery bypass grafting but do not support 2020 American guidelines for performing mitral valve repair or replacement concurrent with aortic valve replacement, with or without coronary artery bypass grafting