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Service-oriented manufacturing (SOM) is a new industrial model that combines manufacturing with service. To enhance the competitiveness of manufacturers in SOM systems, we investigate a coordinated production and delivery scheduling problem considering a third-party logistics (3PL) provider. The considered problem can be divided into two phases, including production phase and delivery phase. In the production phase, jobs are processed by multiple manufacturers located in different geographical zones. Jobs are with deteriorating processing time and set-up time. Several structural properties of the problem in the production phase are proposed, based on which a heuristic algorithm is designed to make decisions on job batching and batch sequencing. After being processed, the finished jobs are immediately delivered to a customer by manufacturers' own vehicles or the 3PL provider. A dynamic programming algorithm is developed to solve the problem in the delivery phase. The integrated scheduling problem is proved to be NP-hard. Hence, we develop a general variable neighbourhood search (GVNS) to solve the problem in a reasonable time. The basic variable neighbourhood descent (BVND) is used as a local search method in the GVNS. Finally, the computational experiments are conducted and the results verify the effectiveness and stability of the proposed approach. [ABSTRACT FROM AUTHOR]

Service-oriented manufacturing has been a prevalent trend in integrating product collaborative development with maintenance service, whereas the final products are frequently trapped into severe quality defects lacking appropriate contracting incentives. This paper establishes a tractable framework investigating the alignment of inspection and warranty strategies to manage product quality throughout the R&D, manufacturing and usage processes. Specifically, the manufacturing effort is motivated by a cost-sharing contract provided by the researcher, who performs quality inspection upon receiving the final product. Subsequent maintenance service is predesignated for warranty period coverage that the cost is partially claimed for compensation from the manufacturer. Under both breakdown and preventive maintenance strategies, we elaborate and compare the optimal incentive intensities solving the equilibrium effort decisions and inspection accuracy. The results suggest that both R&D and manufacturing effort levels under preventive maintenance are slightly higher than that under breakdown maintenance scenario, while inspection accuracy contradicts conversely. The breakdown maintenance strategy is associated with a lower proportion of warranty costs borne by the manufacturer. For a sufficient long warranty period, the researcher is better off to conduct preventive maintenance periodically. Our study contributes to providing explicit implications to manage product development quality with adequate inspection and warranty strategies. [ABSTRACT FROM AUTHOR]

In this study, 17 deoxynivalenol (DON) contaminated wheat samples were assessed for safety and quality index such as unit weight, water absorption of gluten, crude protein content, unsound kernel content, sprouted kernel content, gibberella damaged kernel content and insect infested kernel content as well as the pollution status of DON and heavy metals. Furthermore, the relationship between the content of DON in wheat grains and other parameters was analyzed. The impact of the processing of gluten and starch in the break and reduction systems on the level of DON contamination was examined. The results showed that the pollution level of DON in wheat samples had a good linear correlation with unit weight, water absorption of gluten, crude protein content, unsound kernel content, sprouted kernel content, gibberella damaged kernel content and insect infested kernel content. The correlation between gluten water absorption and the content of DON was not significant, indicating that DON content could not affect the storage quality of wheat. Additionally, it was found that the heavy metals As and Cd as well as the elements Ca and P were not significantly correlated with DON content, but only Ca in whole wheat flour was correlated with the content of DON. The levels of DON in gluten and starch from the break and reduction systems, respectively were both lower than 200 µg/kg, indicating that wheat with DON over-standard can be used commercially for the preparation of gluten or starch.

Creep behavior of P91 steel was studied by using a constitutive model based on deformation mechanism. Combined with the experimental data, it was found that the minimum creep rate has an obvious exponential relationship with the applied stress during creep, which was closely related to different deformation mechanisms. By introducing dislocation slip, dislocation climb and grain boundary slip into the traditional Norton power law equation, the creep behavior of P91 steel under the conditions of 580℃～620℃ and 135 MPa～200 MPa stress was simulated and analyzed. The results show that the creep curve of P91 steel can be well described by using this model, including the initial stage, steady stage and acceleration stage of creep. In addition, the results of model calculation and SEM analysis further show that the creep fracture form of P91 steel is transgranular fracture within the current temperature stress range.

In the traditional farming systems, the excessive application of chemical fertilizers to boost crop yields has resulted in a range of issues, such as soil quality degradation, soil structure deterioration, and pollution of the farmland ecological environment. Green manure, as a high-quality biological fertilizer source with rich nutrient content, is of great significance for enhancing the soil quality and establishing a healthy farmland ecosystem. However, there are few studies on the effects of different green manures on the soil nutrient levels, enzyme activities, and soil bacterial community composition in the rice–wheat rotation areas in southern China. Thus, we planted Chinese milk vetch (MV; Astragalus sinicus L.), light leaf vetch (LV; Vicia villosa var.), common vetch (CV; Vicia sativa L.), crimson clover (CC; Trifolium incarnatum L.), Italian ryegrass (RG; Lolium multiflorum L.), and winter fields without any crops as a control in the Taihu Lake area of Jiangsu. The soil samples collected after tilling and returning the green manure to the field during the bloom period were used to analyze the effects of the different green manures on the soil nutrient content, enzyme activity, and the structural composition of the bacterial community. This analysis was conducted using chemical methods and high-throughput sequencing technology. The results showed that the green manure returned to the field increased the soil pH, soil organic matter (SOM), alkali-hydrolyzed nitrogen (AN), available phosphorus (AP), available potassium (AK), sucrose (SC), urease (UE), and neutral phosphatase (NEP) contents compared to the control. They increased by 1.55% to 10.06%, 0.26% to 9.31%, 20.95% to 28.42%, 20.66% to 57.79%, 12.38% to 37.94%, 3.11% to 58.19%, 6.49% to 32.99%, and 50.0% to 80.36%, respectively. In addition, the green manure field increased the relative abundance of the genera Proteobacteria and Haliangium while decreasing the relative abundance of Gemmatimonadetes, Chloroflexi, SBR1031, and Anaeromyxobacter in the soil bacteria. Both the number of ASVs (amplicon sequence variants) and α-diversity of the soil bacterial communities were higher compared to the control, and the β-diversity varied significantly among the treatments. Alkali-hydrolyzed nitrogen and neutral phosphatase had the greatest influence on the soil bacterial community diversity, with alkali-hydrolyzed nitrogen being the primary soil factor affecting the soil bacterial community composition. Meanwhile, the results of the principal component analysis showed that the MV treatment had the most significant impact on soil improvement. Our study provides significant insights into the sustainable management of the soil quality in rice–wheat rotations. It identifies MV as the best choice among the green manure crops for improving the soil quality, offering innovative solutions for reducing chemical fertilizer dependence and promoting ecological sustainability. [ABSTRACT FROM AUTHOR]