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With the wide application of the service-oriented manufacturing mode, the scale of leasing manufacturing enterprises continues to expand, which leads to the global multi-regional development of maintenance outsourcing services. To address the multi-location maintenance scheduling problem of multi-center leasehold networks in the provision of “products+services”, this paper proposes a multi-center collaboration maintenance scheduling (MCMS) strategy with the dynamic interaction between the system level and the network level. At the system level, it considers the impact of the maintenance downtime, cumulative failure, and system combination selection on maintenance decisions, then optimizes the maintenance grouping of machines in the same manufacturing system. Based on the proposed optimization model, the group maintenance set and the corresponding maintenance start time can be obtained by minimizing the total maintenance cost. At the network level, it further considers the impact of service routing optimization, team dispatch selection, and maintenance response speed on scheduling decision, and then outputs the optimal service route for each team by minimizing the total scheduling cost. It also verifies the feasibility and cost-effectiveness of the MCMS strategy in the field of multi-location maintenance scheduling problems by analyzing the case study.

The remaining oil distribution and displacement mechanism of poly/surface dual flooding stage in medium and high permeability reservoir are not clear. In this paper, the reservoir conditions in Gangxi Area 3 of Dagang Oilfield were taken as the research object. Based on nuclear magnetic resonance and large model physical simulation experiment, the characterization of micro and macro residual oil start-up mechanism and enhanced oil recovery experiment were carried out respectively after polymer flooding poly/surface binary flooding. The experimental results suggest that polymer-surfactant flooding could increase the oil displacement efficiency by 12-29% after polymer flooding, and the contribution of porous to recovery degree is in the order of medium pore, large pore, and small pore. When the surfactant concentration is higher than 0.25%, the increase of oil displacement efficiency tends to be stable, and further enhancing oil recovery requires the expansion of sweep volume. Physical model experiments results show that medium permeability layer has the highest contribution to the recovery degree in the chemical flooding stage, and the displacement mechanism is mainly based on the synergistic effect of expanding sweep volume and improving displacement efficiency. The contribution of low permeability layer to recovery degree is next, and the displacement mechanism is mainly to expand sweep volume. The high permeability layer has the lowest contribution to the recovery degree, and the oil displacement mechanism is mainly to improve the oil displacement efficiency.

Polymer flooding is a tertiary oil recovery technology that is very suitable for the characteristics of China’s reservoirs. However, due to the fast flow rate of polymer solution in near-well zone, the shear effect of perforation blasthole and the compacted zone results in serious loss of polymer viscosity. In this paper, the polymer used in Dagang Oilfield is studied by simulation experiment through the shearing process of perforating holes, and the influence of different perforating parameters on polymer viscosity loss is analyzed, so as to provide theoretical basis for the optimization design of perforating technology in field test. The experimental results show that, the shear effect of perforation blasthole on polymer is not obvious, and the viscosity retention rate of polymer solution is greater than 96%. The size and shape of perforation blasthole have no effect on viscosity loss of polymer solution. The shear effect of compacted zone on polymer is obvious, and the viscosity retention rate of polymer solution is lower than 64% for the target block. The viscosity loss of polymer solution increases with flow rate at compacted zone, and the decrease of permeability can increase viscosity loss of polymer solution. The higher the polymer concentration is, the stronger the shear resistance is, while the higher the molecular weight is, the weaker the shear resistance is. It is suggested that perforation gun and perforation method with deep perforation depth and low compaction degree be chosen to reduce the flow rate at compacted zone and viscosity loss of polymer solution.

The link between infrastructure and green logistics performance in the services sector has been studied in this study. The mediating function of business performance and service quality are also discussed in this study as this is a deductive and cross-sectional study, the hypothesis was first formulated based on the literature gap and then tested. The unit of analysis is management personnel, entry-level economists, and financial analysts. The structural equation modeling-partial least-squares analysis (PLS-SEM) approach was employed in this investigation. The authors validated the reliability and validity of constructs and indicators used to measure constructs by assessing measurement models. The measurement methodology has then utilized to confirm the study hypothesis. The study results demonstrate that infrastructure and green logistics performance have a beneficial influence on services trade and environment; besides that, service quality and company performance are also important factors in improving services trade in China. Furthermore, firm performance and service quality have been identified as strong positive mediators between Green logistic performance, infrastructure, and services trade & environment. This study has a theoretical contribution by introducing, verifying, and proposing a new measurement for three variables: infrastructure, green logistic performance, and services trade & environment. This study has numerous relevant and helpful implications for government agencies and departments. It will provide a pathway for the upcoming industry practitioners in terms of green logistic performance and service trade & environment.

With rapid socio-economic development over the past four decades, a unique tapestry of Chinese society has unfolded into a mosaic of rapid modernization and resurgent patriarchal tradition. Within this complex temporality, parents still remain salient in young Chinese' love and marital life. This study uses data from semi-structured interviews with recently married young people and their parents to investigate how young adults and their parents are involved in the marriage formation process. We found that in this joint process of intergenerational cooperative marriage arrangement, young people and their parents play different roles, as accommodating decision-makers and respectful advisers, respectively. They agreed that a modern marriage based on individual, romantic love was also a union between two families and welcomed their parents' involvement. Moreover, they considered getting married and taking their parents' opinions and preferences into account in their marriage decision as part of their filial piety towards their parents. We have also found that mothers played a salient and significant role in facilitating the transformation of the traditional and distant patriarchal intergenerational relationship into a warm and supportive family union. There are two sides to the mother's role: the entrenchment of the traditional gender roles and the elevation of women's status in the family. [ABSTRACT FROM AUTHOR]