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Purpose: Production planning and control has crucial impact on the production and business activities of enterprise. Enterprise Resource Planning (ERP) is the most popular resources planning and management system, however there are some shortcomings and deficiencies in the production planning and control because its core component is still the Material Requirements Planning (MRP). For the defects of the ERP system, many improvement and optimization schemes have been proposed, and improve the feasibility and practicality of the plan in some extent, but it is fewer studies considering the whole planning system optimization in the multiple performance management objectives and achieving better application performance. The purpose of this paper is to propose a multi-objective production planning optimization model Based on the point of view of the integration of production planning and control, in order to achieve optimization and control of enterprise manufacturing management. Design/methodology/approach: On the analysis of ERP planning system's defects and disadvantages, and related research and literature, a multi-objective production planning optimization model is proposed, in addition to net demand and capacity, multiple performance management objectives, such as on-time delivery, production balance, inventory, overtime production, are considered incorporating into the examination scope of the model, so that the manufacturing process could be management and controlled Optimally between multiple objectives. The validity and practicability of the model will be verified by the instance in the last part of the paper. Findings: The main finding is that production planning management of manufacturing enterprise considers not only the capacity and materials, but also a variety of performance management objectives in the production process, and building a multi-objective optimization model can effectively optimize the management and control of enterprise manufacturing. Practical implications: By setting cost parameters for all kinds of production objectives, mangers can maintain the balances among multiple objectives, and achieve the optimized management and control in the manufacturing process. Originality/value: This paper propose a multi-objective production planning optimization model, which can consider multiple performance management objectives of manufacturing process, and can achieve effective planning and control of production process of enterprise. [ABSTRACT FROM AUTHOR]

Abstract: An air–earth (rock)–tunnel system has often been used for building energy saving. A computing model of the air–earth (rock) heat exchanger is necessary to predict the thermal performance. A numerical simulating model has been developed for the deeply buried air–earth (rock)–tunnel system, in which a 1-D implicit transient convection-diffusion sub-model describes the air temperature and humidity, and a 1-D transient explicit heat conduction sub-model computes the rock temperature. Based on an appropriate discrete scheme, a sequential computing algorithm has been given for solving the air sub-model and the rock sub-model respectively. The accuracy of this numerical model has been verified by comparisons of temperatures of the air and rock and the relative humidity between numerical results and the test data. [Copyright &y& Elsevier]

Under investigation in this manuscript is the coupled Hirota equations, which describe the propagation of ultrashort optical pulses in a birefringent fiber or collision of the two waves arisen by severe weather in deep ocean. Based on the generalized Darboux transformation derived before, we obtain the semirational solutions, and properties of the solitons are discussed in detail: Elastic collisions between/among the two/three solitons on the zero-intensity background are shown in figures, which means that the solitons propagate with the stable amplitudes and velocities during the collisions. Also, inelastic collisions between/among the two/three solitons are illustrated, and some of the solitons travel with amplitudes changed. Furthermore, the bound states among the three solitons are observed. [ABSTRACT FROM AUTHOR]

A series of MCM-41 supported functionalized ionic liquids doped with copper species were prepared, characterized and evaluated as catalysts in the Biginelli reaction. Most of these supported ionic liquids perform well in the reaction, especially the multifunctional copper coordinated MCM-41 supported heterogeneous catalysts (0.5)IL-TiCl 5 @MCM-41@Cu(15) and (0.5)IL-HSO 4 @MCM-41@Cu(15). The catalytic tests revealed that (0.5)IL-HSO 4 @MCM-41@Cu(15) was the best and powerful catalyst in the Biginelli reaction for the preparation of 3,4-dihydropyrimidinones with high to excellent yields. The catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

With the use of RNG k-ε turbulence model, SIMPLEC algorithm and CFD software, the turbulent flow in an axial flow impeller was numerically simulated in the clear water (single-phase) and the sandy water (solid-liquid twophase) conditions. The distributions of solid concentration, velocity and pressure on the impeller of an axial flow pump were analyzed at the same particle diameter but different volume concentrations in sandy water. And these distributions were comparatively analyzed under the clear water and the sandy water conditions. According to the simulation results, the axial pump impeller will be damaged more easily and quickly in sandy water than in clear water. And the area more prone to damage on the axial flow impeller is predicated. The predicted vulnerable parts in an axial flow impeller are consistent with that in actual projects. This study shows that the numerical simulation results are the same as the actual situation, and it has guiding significance for the wear design of the axial flow pump. [ABSTRACT FROM AUTHOR]

A primary factor regulating the composition of the microbial community in the rhizosphere is carbon (C) efflux from root systems, which fundamentally influences microbial functions in the rhizosphere, such as biodegradation, plant growth, and rhizosphere signalling. However, information regarding the incorporation of plant-C by the bacterial community in the rhizosphere is limited, particularly in soybean. Soybean plants were grown in rhizo-boxes containing low- or high-organic C (C org ) Mollisols and labelled with 13 CO 2 at the flowering stage. After soil DNA was extracted from the rhizosphere, 13 C-DNA was separated from 12 C-DNA using the stable isotope probing method, followed by pyrosequencing analysis. Between soils, significant differences in the abundance of genera incorporating 13 C in the rhizosphere were observed, with Aquincola , Dechloromonas , Massilia , Amycolatopsis , Delftia , Magnetospirillum , Psychrobacter , Ochrobactrum , Pseudoxanthomonas and Niastella showing greater relative abundances in low-C org soil ( p < 0.05) compared to high-C org soil. However, the opposite trend was observed for Enhydrobacter , Flavisolibacter , Propionibacterium and Staphylococcus. Correspondingly, the number of operational taxonomic units in each genus varied between soils. Soil type greatly affected the flow of plant-C into rhizospheric bacterial community. The plant-C metabolizing bacteria may contribute to the transformation of rhizodeposits in the soil and soil C sequestration. [ABSTRACT FROM AUTHOR]

Background and aims: Organic amendments are an option in enhancing soil biological productivity. Limited research exists on the effects of long-term cattle manure addition on low-molecular-weight organic acids (LMWOAs) concentrations in corn ( Zea mays L) and soybean ( Glycine max L.) fields in the region of soil erosion. The purpose of this study was to investigate the potential influence of cattle manure on the LMWOAs concentration in erosion soil. Methods: A field experiment was established in Hailun city, Northeast China to determine the impact of long-term cattle manure addition on the total amounts of main LMWOAs in eroded Mollisol fields. There were three levels of simulated-erosion, which removed 0, 10 and 30 cm of topsoil. Two soil amendments were: (1) chemical fertilizer at the rate normally used by farmers in the region and (2) chemical fertilizer plus 15,000 kg ha (dry weight basis) of cattle manure. Main LMWOAs in soil were assessed at the flowering stage of soybean and the jointing stage of corn. Principle results: Compared to chemical fertilizer alone, 7-years of repeated cattle manure addition significantly increased total amounts of main LMWOAs in rhizosphere about 9-70 times and bulk soil about 6-62 times. The magnitude of increase by cattle manure was in the order of oxalate>malate>malonate>lactate>maleate in corn plots, and oxalate>malate>malonate>lactate in soybean plots. In comparison, cattle manure and topsoil removal had larger effect on LMWOAs concentrations in corn plot than soybean plot. The addition of cattle manure application and top soil removal had significant independent influence on main LMWOAs concentration in soil solution. Conclusion: This study suggested that addition of cattle manure would be an effective approach in modifying soil biological properties through the increases in low-molecular-weight organic acids to eroded Chinese Mollisols. [ABSTRACT FROM AUTHOR]

Background: Surgical therapies are the first-line treatments for hepatocellular carcinoma (HCC) patients. However, the high incidence of tumor metastasis after liver surgery remains a severe problem. We aim to investigate the roles and the underlying mechanism of YQ23, stabilized non-polymeric diaspirin cross-linked tetrameric hemoglobin, in liver tumor metastasis after major hepatectomy and partial hepatic ischemia reperfusion (I/R) injury.Methods: An orthotopic liver tumor model in Buffalo rat was established using the hepatocellular carcinoma cell line McA-RH7777. Major hepatectomy for tumor-bearing lobe and partial hepatic I/R injury were performed at two weeks after orthotopic liver tumor implantation. YQ23 (0.2 g/kg) was administered at 1 hour before ischemia and immediately after reperfusion. Blood samples were collected at day 0, 1, 7, 14, 21 and 28 for detection of circulating endothelial progenitor cells (EPCs) and regulatory T cells (Tregs).Results: Our results showed that YQ23 treatment effectively inhibited intrahepatic and lung metastases together with less tumor angiogenesis at 4 weeks after major hepatectomy and partial hepatic I/R injury. The levels of circulating EPCs and Tregs were significantly decreased in YQ23 treatment group. Furthermore, YQ23 treatment also increased liver tissue oxygenation during hepatic I/R injury. Up-regulation of HO1 and down-regulation of CXCR3, TNF-α and IL6 were detected after YQ23 treatment.Conclusions: YQ23 treatment suppressed liver tumor metastasis after major hepatectomy and partial hepatic I/R injury in a rat liver tumor model through increasing liver oxygen and reducing the populations of circulating EPCs and Tregs. [ABSTRACT FROM AUTHOR]