Heterogeneous Network Access Network Selection Algorithm Based on Analytic Hierarchy Process and Improved Variable Weight

Aiming at the problem that the weights of constant weights cannot be changed once they are determined, this paper proposes a network access selection algorithm based on analytic hierarchy process and improved variable weight. The algorithm calculates the weights of indexes based on the analytic hierarchy process, and then introduces the improved punishment variable weight theory. According to user and traffic preferences, the indexes are prioritized. When indexes are flawed, different levels of indexes are subject to different levels of punishment. The algorithm can change the constant weight based on actual parameter values and user preferences, which makes the final decision-making result more scientific and reasonable

Heterogeneous Network Access Network Selection Algorithm Based on Analytic Hierarchy Process and Improved Variable Weight

Aiming at the problem that the weights of constant weights cannot be changed once they are determined, this paper proposes a network access selection algorithm based on analytic hierarchy process and improved variable weight. The algorithm calculates the weights of indexes based on the analytic hierarchy process, and then introduces the improved punishment variable weight theory. According to user and traffic preferences, the indexes are prioritized. When indexes are flawed, different levels of indexes are subject to different levels of punishment. The algorithm can change the constant weight based on actual parameter values and user preferences, which makes the final decision-making result more scientific and reasonable

Network Access Selection Algorithm Based on Balanced Profits between Users and Network

A network access selection algorithm based on the intuitionistic fuzzy analytic hierarchy process (AHP) and bilateral profit drive is proposed in this study for addressing problems regarding user–network bilateral profits. User preference, business demands, and network parameter changes are comprehensively considered in the algorithm. First, the initial weights centered at users are gained by intuitionistic fuzzy AHP. Second, the network participates in network access selection as a subject with competitive consciousness, and the entire selection process is transformed into a multiobjective optimization problem by the construction of a competitive model, thereby obtaining dynamic competitive weights. Third, the initial weights centered at users and the dynamic competitive weights are combined to obtain comprehensive weights. In this way, the dynamic adjustment of comprehensive weights is realized. Finally, candidate networks are ordered according to a comprehensive performance evaluation, and the optimal one is selected. The proposed algorithm is validated by simulation results to be valid in reducing the blocking rate of networks and optimizing network resource allocation. Therefore, it not only protects user–network bilateral profits but also maximizes comprehensive profits

Properties of flash roasted products from low-grade refractory iron tailings and improvement method for their magnetic separation index

The properties of flash-roasted products from low-grade refractory iron tailings (IGRIT) and the improved method for their magnetic separation index were investigated by the MLA, XRD, iron phase analysis, and magnetic separation test. The results show the siderite and hematite in the IGRIT have been converted to magnetic iron after the flash roasting treatment with a time of 3-5 s; magnetic iron in roasted products has a monomeric dissociation of 37.20%, and a 75−100% exposed area of contiguous bodies as rich intergrowth was 29.83%, and that a 32.97 poor intergrowth; moreover, magnetic iron is mainly associated with muscovite and quartz. It is also found that the regrindingmagnetic separation (1500 Oe) treatment of the middling was beneficial to obtain more qualified iron concentrate products. Therefore, roasted products magnetic separation process in the absence/ presence of the middling regrinding-magnetic separation treatment obtains an iron concentrate with 60.10%/ 60.12% iron grade and 72.04%/81.13% iron recovery. The iron concentrate from the magnetic separation process with middling regrinding-magnetic separation can have a 9% higher recovery than the process without middling regrinding-magnetic separation. The work is significant for helping to improve the utilization of IGRIT

A Large-Scale Comparative Metagenomic Study Reveals the Functional Interactions in Six Bloom-Forming Microcystis-Epibiont Communities

Cyanobacterial blooms are worldwide issues of societal concern and scientific interest. Lake Taihu and Lake Dianchi, two of the largest lakes in China, have been suffering from annual Microcystis-based blooms over the past two decades. These two eutrophic lakes differ in both nutrient load and environmental parameters, where Microcystis microbiota consisting of different Microcystis morphospecies and associated bacteria (epibionts) have dominated. We conducted a comprehensive metagenomic study that analyzed species diversity, community structure, functional components, metabolic pathways and networks to investigate functional interactions among the members of six Microcystis-epibiont communities in these two lakes. Our integrated metagenomic pipeline consisted of efficient assembly, binning, annotation, and quality assurance methods that ensured high-quality genome reconstruction. This study provides a total of 68 reconstructed genomes including six complete Microcystis genomes and 28 high quality bacterial genomes of epibionts belonging to 14 distinct taxa. This metagenomic dataset constitutes the largest reference genome catalog available for genome-centric studies of the Microcystis microbiome. Epibiont community composition appears to be dynamic rather than fixed, and the functional profiles of communities were related to the environment of origin. This study demonstrates mutualistic interactions between Microcystis and epibionts at genetic and metabolic levels. Metabolic pathway reconstruction provided evidence for functional complementation in nitrogen and sulfur cycles, fatty acid catabolism, vitamin synthesis, and aromatic compound degradation among community members. Thus, bacterial social interactions within Microcystis-epibiont communities not only shape species composition, but also stabilize the communities functional profiles. These interactions appear to play an important role in environmental adaptation of Microcystis colonies

Trophic Status Is Associated With Community Structure and Metabolic Potential of Planktonic Microbiota in Plateau Lakes

Microbes in various aquatic ecosystems play a key role in global energy fluxes and biogeochemical processes. However, the detailed patterns on the functional structure and the metabolic potential of microbial communities in freshwater lakes with different trophic status remain to be understood. We employed a metagenomics workflow to analyze the correlations between trophic status and planktonic microbiota in freshwater lakes on Yun-Gui Plateau, China. Our results revealed that microbial communities in the eutrophic and mesotrophic-oligotrophic lake ecosystems harbor distinct community structure and metabolic potential. Cyanobacteria were dominant in the eutrophic ecosystems, mainly driving the processes of aerobic respiration, fermentation, nitrogen assimilation, nitrogen mineralization, assimilatory sulfate reduction and sulfur mineralization in this ecosystem group. Actinobacteria, Proteobacteria (Alpha-, Beta-, and Gammaproteobacteria), Verrucomicrobia and Planctomycetes, occurred more often in the mesotrophic-oligotrophic ecosystems than those in the eutrophic ecosystems, and these taxa potentially mediate the above metabolic processes. In these two groups of ecosystems, a difference in the abundance of functional genes involved in carbohydrate metabolism, energy metabolism, glycan biosynthesis and metabolism, and metabolism of cofactors and vitamins significantly contribute to the distinct functional structure of microbiota from surface water. Furthermore, the microbe-mediated metabolic potentials for carbon, nitrogen and sulfur transformation showed differences in the two ecosystem groups. Compared with the mesotrophic-oligotrophic ecosystems, planktonic microbial communities in the eutrophic ecosystems showed higher potential for aerobic carbon fixation, fermentation, methanogenesis, anammox, denitrification, and sulfur mineralization, but they showed lower potential for aerobic respiration, CO oxidation, nitrogen fixation, and assimilatory sulfate reduction. This study offers insights into the relationships of trophic status to planktonic microbial community structure and its metabolic potential, and identifies the main taxa responsible for the biogeochemical cycles of carbon, nitrogen and sulfur in freshwater lake environments

Gas exploration potential of tight carbonate reservoirs: A case study of Ordovician Majiagou Formation in the eastern Yi-Shan slope, Ordos Basin, NW China

On the basis of comprehensive analysis of drilling, gas testing, laboratory analysis and testing data, the characteristics and genesis of tight carbonate reservoirs in Ma51+2 Member of Ordovician Majiagou Formation, eastern Yi-Shan slope, Ordos Basin were examined, and the potential of natural gas exploration and development were analyzed. The tight carbonate reservoir is defined as the reservoir with a porosity of less than 2% and permeability of less than 0.1×10−3 μm2. The Ma51+2 reservoirs are dominantly gypsum mud dolomite, muddy dolomite and Karst-breccia dolomite and has strong heterogeneity, pore types being mainly composed of fracture-dissolution pores and fracture-intercrystalline pores, and thin reservoir layers are distributed in a large area. The unconformity structure adjustment at the top of the Ordovician caused pore creation and pore filling effects, and the joint effect of dissolution pore increase and pore reduction by filling is the major reason for extensive reservoir densification. The thin tight dolomite reservoirs and the overlying adjacent coal source rock in the Upper Paleozoic formed extensive tight carbonate gas with shallow depth (1900−2500 m) and formed a three-dimensional gas containing pattern combined with the Upper Paleozoic tight sandstone gas. The eastern Yi-shan slope in the Ordos Basin has great exploration and development potential. Key words: Ordos Basin, eastern Yi-Shan slope, tight carbonate reservoir, tight gas, exploration potentia

Soil fauna alter the responses of greenhouse gas emissions to changes in water and nitrogen availability

8 páginas.- 5 figuras.- 1 tabla.- referencias.- Supplementary data to this article can be found online at https://doi. org/10.1016/j.soilbio.2023.108990Fertilization and drought are two of the most important global change drivers that impacting greenhouse gas (GHG) emissions. Soil organisms are among the fundamental biotic drivers of biogeochemical cycles and can play critical roles in mitigating global change. However, the contributions of soil macrofauna in explaining the responses of GHG emissions to fertilization and drought remain poorly understood. Here, we designed a three-factor microcosm experiment to examine how soil macrofauna (no fauna, earthworms, and millipedes) alter the responses of CO2, N2O, and CH4 emissions, as well as the C and N contents in response to contrasting levels of N (N0: without N addition, N+: N addition) and available soil water (40% and 60% of soil water holding capacity). We show that soil fauna were significant regulators of CO2 and N2O emissions in response to changes in water and N availability, as supported by multiple identified statistical interactions. Millipedes were observed to reduce the positive influence of soil water availability on soil CO2 emissions in response to the addition of N. Similarly, earthworms weakened the effects of elevated N and water availability on soil N2O emissions. Moreover, CH4 emissions occurred only when millipedes were present. The structural equation models revealed that earthworms and millipedes modified soil CO2 and N2O emissions through their influences on soil total dissolved nitrogen and microbial biomass carbon. Overall, this study demonstrated that soil macrofauna can notably mediate the responses of GHG emissions and soil biogeochemical cycles to global environmental changes.This study was supported by the National Natural Science Foundation of China (Grant No. 32101339 and 32071594), and partially by the National Key Research and Development Program of China (2021YFD2200403, 2016YFD0600204) and the Key Subject of Ecology of Jiangsu Province (SUJIAOYANHAN❲2022❳No.2). M.D-B. acknowledges support from the Spanish Ministry of Science and Innovation for the I + D + i project PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033. M.D-B. is also supported by a project of the Fondo Europeo de Desarrollo Regional (FEDER) and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014–2020 Objetivo temático “01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación”) associated with the research project P20_00879 (ANDABIOMA). HYHC acknowledges support from the Natural Sciences and Engineering Research Council of Canada (RGPIN-2019–05109 and STPGP506284) and the Canada Foundation of Innovation and Ontario Research Fund (CFI36014).Peer reviewe