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A new method to evaluate integrated production system capacity in oil fields
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作者 YADUA Asekhame U. LAWAL Kazeem A. 《Petroleum Exploration and Development》 SCIE 2023年第3期665-674,共10页
To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the cons... To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the conservation laws with applicable multiphase fluid and choke models,these mathematical models are solved to characterize the hydraulics of an integrated system of reservoir,wells,chokes,flowlines,and separator at steady state.The controllable variables such as well count,choke size and separator pressure are adjusted to optimize the performance of the IPs at a specific time.It is found that increasing the well count can increase the bulk flow rate of the production network,but too many wells may increase the manifold pressure,leading to decline of single-well production.Increasing the choke size can improve the capacity of the IPs.The production of the IPs is negatively correlated with the separator pressure.With increasing separator pressure and decreasing choke size,the increment of total fluid production(the capacity of IPS)induced by increasing well count decreases.Validation tests with field examples show a maximum absolute deviation is 1.5%,demonstrating the robustness and validity of the proposed mathematical models and workflows. 展开更多
关键词 integrated production system modelling integrated production system capacity productivity evaluation production optimization nodal analysis
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Research on the improved cooperative cellular system capacity
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作者 陈惠民 解维浩 +2 位作者 王亮 武卓 金彦亮 《Journal of Shanghai University(English Edition)》 CAS 2011年第2期85-88,共4页
Recently, the multi-hop cellular networks have been widely studied in order to enhance the cell performances such as the cell capacity. While most of these works merely use the multi-hop methods instead of direct tran... Recently, the multi-hop cellular networks have been widely studied in order to enhance the cell performances such as the cell capacity. While most of these works merely use the multi-hop methods instead of direct transmission without considering the co-channel inter-cell interference, signal transmission mode and the effects of the number of antennas. With the consideration of above important elements, this paper proposed an improved cellular system with multi-relay amplifies-andforward (AF) cooperative transmission scheme and the corresponding capacity expression is derived under the corresponding environment. By using the potential space diversity and selecting relays based on maximizing the capacity, the cellular system capacity can be improved effectively. The simulation results show that with the assistance of optimal selected relays, the improved cooperative cellular system capacity with multi-relay AF transmission scheme performs better than single-hop cellular system. 展开更多
关键词 cooperative scheme amplifies-and-forward (AF) transmission cellular system system capacity
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PV Capacity Evaluation Using ASTM E2848: Techniques for Accuracy and Reliability in Bifacial Systems
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作者 Gautam Swami Kajal Sheth Dhvanil Patel 《Smart Grid and Renewable Energy》 2024年第9期201-216,共16页
A variety of test methodologies are commonly used to assess if a photovoltaic system can perform in line with expectations generated by a computer simulation. One of the commonly used methodologies across the PV indus... A variety of test methodologies are commonly used to assess if a photovoltaic system can perform in line with expectations generated by a computer simulation. One of the commonly used methodologies across the PV industry is an ASTM E2848. ASTM E2848-13, 2023 test method provides measurement and analysis procedures for determining the capacity of a specific photovoltaic system built in a particular place and in operation under natural sunlight. This test method is mainly used for acceptance testing of newly installed photovoltaic systems, reporting of DC or AC system performance, and monitoring of photovoltaic system performance. The purpose of the PV Capacity Test and modeled energy test is to verify that the integrated system formed from all components of the PV Project has a production capacity that achieves the Guaranteed Capacity and the Guaranteed modeled AEP under measured weather conditions that occur when each PV Capacity Test is conducted. In this paper, we will be discussing ASTM E2848 PV Capacity test plan purpose and scope, methodology, Selection of reporting conditions (RC), data requirements, calculation of results, reporting, challenges, acceptance criteria on pass/fail test results, Cure period, and Sole remedy for EPC contractors for bifacial irradiance. 展开更多
关键词 Photovoltaic system capacity ASTM E2848 Bifacial PV Modules PV capacity Testing PVSyst Simulation Solar Energy Performance Regression Modeling
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The system capacity view of aging and longevity
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作者 Jing-Dong J. Han Lei Hou +3 位作者 Na Sun Chi Xu Joseph McDermott Dan Wang 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2017年第3期251-259,共9页
Background: Aging is a complex systems level problem that needs a systems level solution. However, system models of aging and longevity, although urgently needed, are still lacking, largely due to the paucity of conc... Background: Aging is a complex systems level problem that needs a systems level solution. However, system models of aging and longevity, although urgently needed, are still lacking, largely due to the paucity of conceptual frameworks for modeling such a complex process. Results: We propose that aging can be viewed as a decline in system capacity, defined as the maximum level of output that a system produces to fulfill demands. Classical aging hallmarks and anti-aging strategies can be well-aligned to system capacity. Genetic variants responsible for lifespan variation across individuals or species can also be explained by their roles in system capacity. We further propose promising directions to develop systems approaches to modulate system capacity and thus extend both healthspan and lifespan. Conclusions: The system capacity model of aging provides an opportunity to examine aging at the systems level. This model predicts that the extent to which aging can be modulated is normally limited by the upper bound of the system capacity of a species. Within such a boundary, aging can be delayed by moderately increasing an individual's system capacity. Beyond such a boundary, increasing the upper bound is required, which is not unrealistic given the unlimited potential of regenerative medicine in the future, but it requires increasing the capacity of the whole system instead of only part of it. 展开更多
关键词 systemS system capacity AGING LONGEVITY
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Satellite and high altitude platform-based inter-vehicle communications in vast and desolate areas 被引量:1
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作者 林元乖 王琳 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期135-139,共5页
In order to solve the problem of inter-vehicle communication (IVC) in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the... In order to solve the problem of inter-vehicle communication (IVC) in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the other is based on high altitude platform ( HAP ) communication. The system outline and networking modes of the two models are described. In the satellite communication based model, all the vehicles are equipped with vehicle-bone satellite communication on the move terminals and the communication signals between vehicles are forwarded by satellite. In the high altitude platform-based model, the HAPs are equipped with base station facilities to form aerial base stations, and vehicles can communicate with each other via common terrestrial mobile communication devices. Some key parameters such as path loss, link loss and system capacity are also computed. The analysis shows that both the two models can satisfy the requirement of IVC in the descriptive environment. 展开更多
关键词 inter-vehicle communication satellite communication high altitude platform communication terrestrial mobile communication device system capacity
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Coping with the Big Data:Convergence of Communications,Computing and Storage 被引量:2
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作者 Pingzhi Fan 《China Communications》 SCIE CSCD 2016年第9期203-207,共5页
To cope with the impact of big data,it is proposed to integrate the traditionally individual computing,communications and storage systems,which are getting inevitably converged.An effective information system capacity... To cope with the impact of big data,it is proposed to integrate the traditionally individual computing,communications and storage systems,which are getting inevitably converged.An effective information system capacity is introduced and discussed,aimed at excavating potentials of information system under a new paradigm with more degrees of freedom. 展开更多
关键词 big data COMMUNICATIONS com- puting STORAGE information system capacity
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The Capacity Analysis of the CDMA Cellular System 被引量:1
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作者 Zhang Ping(Department of Telecommunication Engineering,Beijing University of Posts and Telecommunications,Beijing 100088,P.R.China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 1996年第1期1-7,14,共8页
This paper analyzes the CDMA cellular system in which the practical power control processwith errors is modeled as random log-normally distributed variable at the reverse link. The Performance of the CDMA system is me... This paper analyzes the CDMA cellular system in which the practical power control processwith errors is modeled as random log-normally distributed variable at the reverse link. The Performance of the CDMA system is measured in terms of outage probability,and the computing results arepresented in this paper.This work is useful for CDMA system designation and provides the criteria forevaluating CDMA System capacity in a more practical way. 展开更多
关键词 s:CDMA power control system capacity antenna sector
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OPTIMAL POWER ALLOCATION WITH AF AND SDF STRATEGIES IN DUAL-HOP COOPERATIVE MIMO NETWORKS
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作者 Xu Xiaorong Zheng Baoyu Zhang Jianwu 《Journal of Electronics(China)》 2010年第3期328-339,共12页
Dual-hop cooperative Multiple-Input Multiple-Output (MIMO) network with multi-relay cooperative communication is introduced. Power allocation problem with Amplify-and-Forward (AF) and Selective Decode-and-Forward (SDF... Dual-hop cooperative Multiple-Input Multiple-Output (MIMO) network with multi-relay cooperative communication is introduced. Power allocation problem with Amplify-and-Forward (AF) and Selective Decode-and-Forward (SDF) strategies in multi-node scenario are formulated and solved respectively. Optimal power allocation schemes that maximize system capacity with AF strategy are presented. In addition, optimal power allocation methods that minimize asymptotic Symbol Error Rate (SER) with SDF cooperative protocol in multi-node scenario are also proposed. Furthermore, performance comparisons are provided in terms of system capacity and approximate SER. Numerical and simulation results confirm our theoretical analysis. It is revealed that, maximum system capacity could be obtained when powers are allocated optimally with AF protocol, while minimization of system's SER could also be achieved with optimum power allocation in SDF strategy. In multi-node scenario, those optimal power allocation algorithms are superior to conventional equal power allocation schemes. 展开更多
关键词 Dual-hop cooperative Multiple-Input Multiple-Output (MIMO) network Optimal power allocation Amplify-and-Forward (AF) Selective Decode-and-Forward (SDF) system capacity Asymptotic Symbol Error Rate (SER)
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Queue Size Distribution of Geo/G/1 Queue Under the Min(N,D)-Policy 被引量:14
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作者 GU Jianxiong WEI Yingyuan +1 位作者 TANG Yinghui YU Miaomiao 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第3期752-771,共20页
This paper considers a discrete-time Geo/G/1 queue under the Min(N, D)-policy in which the idle server resumes its service if either N customers accumulate in the system or the total backlog of the service times of ... This paper considers a discrete-time Geo/G/1 queue under the Min(N, D)-policy in which the idle server resumes its service if either N customers accumulate in the system or the total backlog of the service times of the waiting customers exceeds D, whichever occurs first (Min(N, D)-policy). By using renewal process theory and total probability decomposition technique, the authors study the transient and equilibrium properties of the queue length from the beginning of the arbitrary initial state, and obtain both the recursive expression of the z-transformation of tile transient queue length distribution and the recursive formula for calculating the steady state queue length at arbitrary time epoch n+. Meanwhile, the authors obtain the explicit expressions of the additional queue length distribution, l^trthermore, the important relations between the steady state queue length distributions at different time epochs n , n and n+ are also reported. Finally, the authors give numerical examples to illustrate the effect of system parameters on the steady state queue length distribution, and also show from numerical results that the expressions of the steady state queue length distribution is important in the system capacity design. 展开更多
关键词 Min(N D)-policy discrete-time queue queue length distribution system capacity opti mum design total probability decomposition technique z-transform.
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Pay attention to situation of SARS-CoV-2 and TCM advantages in treatment of novel coronavirus infection 被引量:6
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作者 Chang-xiao Liu 《Chinese Herbal Medicines》 CAS 2020年第2期97-103,共7页
Since the outbreak of the new coronavirus epidemic,novel coronavirus has infected nearly 100,000 people in more than 110 countries.How to face this new coronavirus epidemic outbreak is an important issue.Basic reprodu... Since the outbreak of the new coronavirus epidemic,novel coronavirus has infected nearly 100,000 people in more than 110 countries.How to face this new coronavirus epidemic outbreak is an important issue.Basic reproduction number(R0)is an important parameter in epidemiology;The basic reproduction number of an infection can be thought of as the expected number of cases directly generated by one case in a population where all individuals are susceptible to infection.Epidemiology dynamics is a mathematical model based on a susceptibility-infection-recovery epidemic model.Researchers analyzed the epidemiological benefits of different transmission rates for the establishment of effective strategy in prevention and control strategies for epidemic infectious diseases.In this review,the early use of TCM for light and ordinary patients,can rapidly improve symptoms,shorten hospitalization days and reduce severe cases transformed from light and normal.Many TCM formulas and products have wide application in treating infectious and non-infectious diseases.The TCM theoretical system of treating epidemic diseases with TCM and the treatment scheme of integrated Chinese and Western medicine have proved their effectiveness in clinical practice.TCM can cure COVID-19 pneumonia,and also shows that the role of TCM in blocking the progress of COVID-19 pneumonia. 展开更多
关键词 basic reproduction number COVID-19 epidemiology dynamics national healthcare system capacity novel Coronavirus Infection SARS-CoV-2 TCM advantages
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