A new method to evaluate integrated production system capacity in oil fields

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.

Research on the improved cooperative cellular system capacity

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.

The system capacity view of aging and longevity

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.

The Capacity Analysis of the CDMA Cellular System

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.

OPTIMAL POWER ALLOCATION WITH AF AND SDF STRATEGIES IN DUAL-HOP COOPERATIVE MIMO NETWORKS

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.

Pay attention to situation of SARS-CoV-2 and TCM advantages in treatment of novel coronavirus infection

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.