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Community detection in complex network has been an active research area in data mining and machine learning. This paper proposed a community detection method based on multi-objective evolutionary algorithm, named CDMOEA, which tries to find the Pareto front by maximize two objectives, community score and community fitness. Fast and Elitist Multi-objective Genetic Algorithm is used to attained a set of optimal solutions, and then use Modularity function to choose the best one from them. The locus based adjacency representation is used to realize genetic representation, which ensures the effective connections of the nodes in the network during the process of population Initialization and other genetic operator. Uniform crossover is introduced to ensure population’s diversity. We compared it with some popular community detection algorithms in computer generated network and real world networks. Experiment results show that it is more efficient in community detection.

In the rock pyrolysis experiment, part of the boiling point above 300°C of the high carbon number hydrocarbons and the hydrocarbon generated from pyrolysis of resin and asphaltene detected into S₂, resulting in the thermolysis residual hydrocarbon "S₁" is smaller than the real value, potential hydrocarbon generation of kerogen "S₂" is greater than the real value. Thus using the experimental pyrolysis parameters directly calculate the hydrocarbon expulsion efficiency is greater than the real value. We used the pyrolysis parameters before and after correction, combined with the method of the restoring of original hydrocarbon potential to calculate the hydrocarbon expulsion efficiency of mudstone of Qingshankou l member of well Xu 11 in San Zhao area of Song Liao Basin. The average of the expulsion efficiency before and after the pyrolysis parameters correction are 87.4% and 66.9%. The hydrocarbon expulsion efficiency have a great difference between before and after correction, thus the pyrolysis parameters correction is particularly important in the calculation of hydrocarbon expulsion efficiency.

Desorption of Coalbed Methane is one of the key controls to CBM recovery ratio and production capacity. This paper discusses the impact of engineered measures on CBM overall desorption and production capacity with CBM model of Eclipse numerical simulation software. The simulation results show that: with the extension of hydraulic fracture half-length, overall desorption of coal reservoir increased and CBM production capacity improved, daily gas production, maximum gas production and stable yield time increased correspondingly; in different deployment of spacing and well network, the smaller spacing is beneficial to the overall desorption of coal reservoir, but its production can not keep stability because of the serious decline in the late stage of development, while the larger spacing shows in the opposite way.

Sr₂NaNb₅O₁₅ ceramic powders have been synthesized by sol-gel method, ceramics were sintered via a pressureless sintering method. The effect of calcining temperature on the phase composition and microstructure of ceramic powders were investigated by TG-DSC, XRD and SEM analyses. The influence of sintering temperature on density, microstructure and properties of the ceramics were systematically analyzed. The results showed that the optimal calcining temperature was 1300°C, the average size of ceramic powders was about 3μm. When the sintering temperature was 1300°C, the ceramics showed optimized densification and electrical properties(ρ=4.663 g/cm³, d₃₃=45 pC/N, εr=1126, tan=0.027, Ec=17.91 kV/cm, Pr=6.72 μC/cm², Ps=9.45 μC/cm²)

Catalytic hydrolysis decomposition of dichlorodifluoromethane (CCl₂F₂) in the presence of water vapor and oxygen was studied over solid base Na₂O/ZrO₂ using a fixed-bed reactor. The CCl₂F₂ adsorption was multilayer chemical adsorption and its process was corresponding with Freundlich model. Its adsorption heat was from 43.74 to 76.31 KJ.mol^-1, and the CCl₂F₂ adsorption over solid base Na₂O/ZrO₂ was exothermic and chemical.

Highly ordered TiO₂ nanotube array hasbeen widely used as the dye-sensitized solar cells’ (DSSCs) light anode material forits abilities of inhibiting electronic recombination at the interface and improving the beam transmission of the carrier. The morphology and structure of the nanotube would influence the efficiency of the cell. In thisstudy, TiO₂ nanotubes (caliber ranging from 50 to 150nm, length ranging from 0.9 to 4μm) were prepared by a two-step anodization method and the morphology of nanotubes was regulated bythe parameters such as oxidation voltage and oxidation time. The absorbing capacities of nanotubes were measured by the dye adsorption test and the corresponding photoelectric conversion efficienciesweremeasured too. The results indicated that the conversion efficiency was related to the specific surface area and length of the nanotube. The length of nanotube would increase with theoxidation time within acertain limit.Then thedissolution on the top of TNT would reduce nanotubes’ length and lead to the decrease of the specific area, eventuallyimpairedthe photoelectric conversion.

The graphite was exfoliated by concentrated acid treatment, strong oxidants oxidation, high temperature rapid thermal shock process. Investigated in detail that the kind of oxidants, concentrated acid ratio, oxidation time affected on the graphite expansion rate. Experimental results (expansion, micro-structure observation and chemical structure analysis of graphite) showed that the optimum volume ratio of concentrated sulfuric acid and concentrated nitric acid was 4:1; the expansion rate was better that added oxidant KMnO₄ than added oxidant K₂Cr₂O₇; The best oxidation time (concentrated acid treatment time) was 30~60 min.

Aviation ad hoc network has dynamic topology and uneven distribution of nodes, so it is difficult to establish node-disjoint multipath routes. Aviation ad hoc network multipath routing of path segmentation based build multipath routes between source node and the destination node in path segmentation. Each segmentation has one to three concurrent paths established by the topology of network, through which it leads to loading equilibrium. To ensure the accuracy of the data transmission of links with hop-by-hop verifying transmission mechanism and to reduce the cost of frequently routing update and end-to-end delay with routing fragment strategy. Finally, the routing protocol is simulated with the simulation software NS2 and the result shows that it has a good performance.

Application of probabilistic risk assessment (PRA) and deterministic risk assessment (DRA) at a coking plant site were compared. By DRA, Hazard Quotient (HQ) following exposure to Naphthalene (Nap) and Incremental Life Cancer Risk (ILCR) following exposure to Benzo(a)pyrene (Bap) are 1.87 and 2.12×10^-4. PRA reveals valuable information regarding the possible distribution of risk, and the outputs show that Nap HQ ranges from 6.18×10^-7 to 6.62 and Bap ILCR ranges from 8.67×10^-10 to 6.89×10^-4. Risk estimates of DRA locates at the 99.59th and 99.76th percentiles in the risk outputs of PRA, indicating the DRA overestimates the risk. Sensitivity analysis was done by calculating a contribution to variance for each exposure parameter and it is found that contaminant concentration in the soil (C_s), exposure duration (ED), soil ingestion rate (IR_s) are the most important parameters for risk calculations

In order to resolve problem of integration of SAP(super absorbent polymer) and fertilizer, in this paper, controlled-release SAP was applied to research the rule of apparent uptake on the nitrogen, phosphorus and kalium nutrient elements by method of nutrient standardization which can provide for theory basis. The result showed that all different treatments on annual lolium perenne had a positive in absorbing nitrogen elements; between kalium and phosphorus nutrition elements had significant negative correlation, correlation coefficient above-0.90.Treatments of FER and YFISJ greatly improved content of nitrogen, phosphorus nutrition elements in lolium perenne, but also were greatly reduce to kalium element absorption. Meanwhile, treatments of different particle sizes of SAP improved obviously absorption of nitrogen and kalium element, phosphorus element of absorption was inhibited. Compound SAP improve nitrogen element apparent top utilization rate of 197%, improve phosphorus element apparent top utilization rate reaches 183% hydration, but reduces the kalium element absorption topped - 187%. The conclusions show that nutrients standardization method cans effective to compare and analysis with nutrients uptake among different treatments. Homemade controlled-release SAP can dramatically improve part of nutrition utilization.