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With increasing wind energy integrated into power systems, the topic of economic dispatch (ED) becomes more important. In this paper, a risk constrained ED (RCED) model is proposed, which aims to obtain the optimal dispatch solution to balance the economic gain and the economic risk brought by uncertain wind power. Then Pareto-based multi-objective optimization approach is applied to optimize the gain and risk under the uncertain environment, simultaneously. Afterwards, an improved optimization algorithm, chaotic group search optimizer with multiple producers (CGSOMP) is used for solving this complex problem. Simulation studies are conducted on a modified IEEE 30-bus power system, and results verify outperformance of the RCED model, compared with the traditional ED approach. [ABSTRACT FROM AUTHOR]

Abstract: A hard Cr-deposit was annealed at 250°C for various periods after electroplating. From the results of the DSC analysis and hardness measurement, the softened microstructure in the Cr-deposit was developed after 30min annealing. By examining the TEM-cross-sectional annealed specimen, a recrystallization zone of the soften microstructure was found, in which equiaxed grains with relative lower dislocation density were examined from place to place and many voids were found among the triple grain boundary. However, most parts of as-plated Cr-deposit grew slightly and were still in texture after long-term annealing at 250°C. On the interface between the Cr-deposit and the steel initiated equiaxed grains that grew by merging adjacent grain and small angle grain boundary were observed. [Copyright &y& Elsevier]

The electrochemical behavior of tin-doped indium oxide (ITO) on SiO2 in 0.3 M HCl was studied using voltammetric scanning method. The result showed that an obvious reduction current peak occurred during the first cathodic potential scanning. The reduction reaction became less active after annealing ITO at 500 °C for 1 h. The result was attributed to the replenishment of oxygen-deficient site, which acts as current carrier, by the annealing treatment. Many spherical In–Sn particles with sizes about 100–500 nm were formed on the ITO surface adjacent to the grain boundary when the reduction current took place. The In–Sn particles initiated preferentially on the ITO surface near grain boundaries attending the dissolution of ITO grain boundary. In the scanning period, after completion of the reduction current peak, reduction of hydrogen ions occurred in more negative potential region. A schematic illustration for the formation mechanism of the In–Sn reduction particle was postulated based on the metallographical and electrochemical results in this work. [Copyright &y& Elsevier]

Abstract: A new two-dimensional network model is proposed as a micromechanics model to simulate paper’s failure process due to sequentially breakages of fibers and/or bonds. Paper is approximated as a network composed of fibers any two of which link to each other by their intersecting point, namely so-called bond. Fibers distribute along three particular directions, leading to network’s macro-level isotropy. In the framework of finite element method, nodes correspond to fiber-to-fiber bonds, while elements are fiber segments between every two neighboring nodes and described by Timoshenko beam theory. Element breaks when its equivalent internal tensile stress reaches the tensile strength of fiber. Strength of nodes, i.e. fiber-to-fiber bonds is assumed to be dependant on shearing interaction between fibers, considering the dominant interaction is shearing in a plane problem. Numerical examples show the model’s capacity of reflecting basic failure characteristic in paper. Influences of fiber length and the ratio of fiber strength to bond strength are analyzed in detail. [ABSTRACT FROM AUTHOR]

• AgNPs cross-linked within glass ionomer cement (GIC) matrices generated antibiofilm effects at the nanocomposite surface. • AgNP-containing GICs had higher compressive strengths and equivalent flexural strengths to unmodified GICs. To develop a silver nanoparticle (AgNP) formulation for incorporation into glass ionomer cements (GICs) which minimises biofilm growth on restoration surfaces. GICs, Fuji IX, Ketac Molar, and Riva Selfcure were modified with 6, 10 and 24 μg per GIC capsule of α-lipoic acid-capped AgNPs. Monoculture biofilms of Streptococcus mutans were cultured (72 h) on GIC specimens (n = 3) and biofilm accumulation was quantified using a viability stain with confocal laser scanning microscopy. Compression strength and flexural strength (CS & FS) were measured according to ISO 9917-1:2007 (n = 8, n = 25). GIC colour was measured at 0, 1, and 14 days following AgNP incorporation using a digital spectrophotometer. Silver release from AgNP-modified GIC specimens was monitored at 1, 3, 7 and 14 days using inductively coupled plasma-mass spectrometry. AgNP-modified Fuji IX demonstrated the greatest reduction in biofilm accumulation, with 10 μg Ag/capsule inhibiting biofilm formation by 99%. Ketac Molar and Riva Selfcure required 24 μg Ag/capsule to achieve 78% biofilm reduction. AgNP-modified GICs demonstrated significantly higher CS and FS than sintered silver-containing GICs, and possessed equivalent or higher strength values when compared to unmodified GICs. The colour shades of AgNP-modified GICs were more comparable to VITA shades of non-modified GICs than were sintered silver-containing GICs. The silver (≥99.6%) remained within the GIC for at least two weeks following incorporation. AgNP-modified GICs exhibited significant antibiofilm activity and retained mechanical properties equivalent or superior to non-modified GICs. AgNP-modified GICs could reduce bacterial colonisation on and around restorations thereby reducing restoration failure caused by secondary caries. [ABSTRACT FROM AUTHOR]

The decision support model of mean-lower semi-absolute deviation (MLSAD) and the optimization algorithm of group search optimizer with intraspecific competition and lévy walk (GSOICLW) are presented to solve wind-thermal power system dispatch. MLSAD model takes the profit and downside risk into account simultaneously brought by uncertain wind power. Using a risk tolerance parameter, the model can be converted to a single-optimization problem, which is solved by an improved optimization algorithm, GSOICLW. Afterwards, both the model and the algorithm are tested on a modified IEEE 30-bus power system. Simulation results demonstrate that the MLSAD model can well solve wind-thermal power system dispatch. The study also verifies GSOICLW obtains better convergent dispatching solutions, in comparison with other evolutionary algorithms, such as group search optimizer and particle swarm optimizer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Study the crystallographic and nanomechanical properties of two bryozoan species. • Species adapt their skeletal ultrastructure for different marine environments. • Branch morphology controls crystallite orientations, hardness and elasticity. • Anisotropic skeleton of H. currieae designed to withstand higher water pressures. • Isotropic skeleton of H. robusta designed against predators and stronger currents. This study examines how microscale differences in skeletal ultrastructure affect the crystallographic and nanomechanical properties of two related bryozoan species: (i) Hornera currieae, which is found at relatively quiescent depths of c. 1000 m, and (ii) Hornera robusta, which lives at depths of 50–400 m where it is exposed to currents and storm waves. Microstructural and Electron Backscatter Diffraction (EBSD) observations show that in both species the secondary walls are composed of low-Mg calcite crystallites that grow with their c-axes perpendicular to the wall. Branches in H. currieae develop a strong preferred orientation of the calcite c-axes, while in H. robusta the c-axes are more scattered. Microstructural observations suggest that the degree of scattering is controlled by the underlying morphology of the skeletons: in H. currieae the laminated branch walls are smooth and relatively uninterrupted, whereas the wall architecture of H. robusta is modified by numerous deflections, forming pustules and ridges associated with microscopic tubules. Modelling of the Young's modulus and measurements of nanoindentation hardness indicate that the observed scattering of the crystallite c-axes affects the elastic modulus and nanohardness of the branches, and therefore controls the mechanical properties of the skeletal walls. At relatively high pressure in deep waters, the anisotropic skeletal architecture of H. currieae is aimed at concentrating elasticity normal to the skeleton wall. In comparison, in the relatively shallow and active hydrographic regime of the continental shelf, the elastically isotropic skeleton of H. robusta is designed to increase protection from external predators and stronger omni-directional currents. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of different dietary levels of cassava starch extraction residue meal (CReM) on egg production, egg quality, oxidative status, egg yolk fatty acid profile, and hepatic expression of fatty acid metabolism-related genes. In total, 288 Longyan laying ducks aged 21 wk with similar BW were randomly assigned to 4 dietary treatments, each consisting of 6 replicates of 12 birds. The birds were fed a typical corn-soybean meal diet, which contained 0% (control), 5%, 10%, and 15% CReM, mainly replacing wheat bran, and the experiment lasted for 16 wk. The tested CReM levels did not show significant effects on the egg production, nonmarketable egg percentage, egg weight, daily egg mass, and FCR (g feed: g egg), but daily feed intake was reduced with increased CReM level (linear P < 0.001, quadratic P < 0.05). Yolk color increased (linear and quadratic, P < 0.01) with the increase in CReM level, but the Haugh unit, yolk proportion, albumen proportion, shell proportion, eggshell thickness, and eggshell strength were unaffected. Yolk contents of C11:0 and C12:0 (linear, quadratic, P < 0.01) and total saturated fatty acids increased, and the C22:1 level decreased (linear P < 0.01, quadratic P < 0.05) with the increase in CReM level, but the total monounsaturated fatty acids, the individual and total polyunsaturated fatty acids and n−6 and n−3 fatty acids, triglycerides, and total cholesterol in egg yolk were not affected. Hepatic gene expression revealed a significant increase in peroxisome proliferators-activated receptors γ (linear, quadratic, P < 0.001), but the expression of fatty acid synthase, sterol regulatory element binding protein 1 and apolipoprotein A1 genes were unaffected by CReM level. In conclusion, the results of the current study indicated that the CReM could be included up to 15% in laying duck diets without negative effects on the egg-laying rate, egg quality, and oxidative status. Dietary inclusion of CReM increased the yolk content of total saturated fatty acids and SOD activity in the liver. [ABSTRACT FROM AUTHOR]

Abstract: Micromechanical modeling of three-dimensional (3D) fiber networks is performed by reducing the web structure to fiber segments and fiber–fiber bonds to explore the influence of fiber–fiber bond deformability on fiber network’s elasto-plasticity. The fiber segment between every two adjacent bonds is described by a Timoshenko beam element, while fiber–fiber bonds are taken as a different two-node element due to the extremely large height-to-span ratio. This overcomes the rigid-bond assumption employed by most previous network models, providing the feasibility to build the relationship between bonding condition and global mechanical properties, resulting in a 3D network structure and able to accommodate curled fibers. Both fibers and bonds are assumed to be elasto-plastic and described by the bilinear kinematic hardening model. Deformation of the network with load increasing is simulated by the Newton–Raphson method. Numerical tensile tests show reasonable results and agree qualitatively with experiments. The influence of bond deformability on the mechanical behavior of the network is discussed in detail. [Copyright &y& Elsevier]

This study aimed to compare the effects of inorganic and organic manganese (Mn) supplementation on productive performance, egg quality, tibial characteristics, serum biochemical indices, and Mn excretion in laying ducks. A total of 756 Longyan laying ducks (45 wk) were randomly assigned to 9 treatments, each with 6 replicates of 14 ducks. Ducks were fed a basal diet (30.6 mg Mn/kg) or that basal diet supplemented with 20, 40, 80, and 160 mg/kg Mn using inorganic (added as MnSO 4 ·H 2 O) or organic (Mn-methionine; 8% Mn, 76% methionine) for 20 wks. Supplementation with inorganic Mn increased egg production and mass, and decreased FCR after 10 wk of feeding, and there were quadratic responses between them, and improved performance was observed with 40 mg/kg supplementation (P < 0.05). Supplementing with organic Mn, however, only increased egg production during wk 6–10 (P < 0.05), but FCR decreased linearly (P < 0.05, wk 16–20) with supplemental levels. Egg production and mass were higher with the addition of inorganic than organic Mn during wk 11–15 (P < 0.05). At wk 10, supplemental inorganic or organic Mn increased egg albumen height and Haugh unit, and with quadratic responses, and higher values were obtained with 40 mg/kg inorganic Mn supplementation (P < 0.05). Ducks supplemented with organic Mn had higher eggshell fracture toughness than that of ducks fed the basal diet or those containing inorganic Mn, and organic Mn linearly increased shell breaking strength at wk 10 (P < 0.05). Supplemental inorganic or organic Mn both increased mineral density and content, fresh and fat-free dry weight, length, calcium and Mn content of the tibias (P < 0.05), and mineral density, calcium and Mn content of tibias were higher in the ducks given organic than inorganic Mn (P < 0.05), and their values were higher with the supplementation of 80 mg/kg inorganic Mn and 20 mg/kg organic Mn (P < 0.05). Supplementation with Mn increased Mn excretion and with linear and quadratic effects, and excretion was lower with organic than inorganic Mn (P < 0.05). Overall, supplementation with inorganic Mn increased productive performance, but the benefits of organic Mn were less obvious. Both inorganic and organic Mn increased tibial characteristics and Mn excretion, with organic Mn being more effective or lower excretion. Taken together, it can be suggested that 40 ~80 mg/kg Mn from an inorganic source or 20 mg/kg Mn from an organic source would be appropriate when laying ducks were fed a typical corn-soybean meal diet (with 30.6 mg/kg basal Mn) during the laying period (45–64 wk of age). • The effect of inorganic and organic Mn supplementation (20-160 mg/kg) in laying duck diet were determined in a 20-wk feeding trial. • Inorganic Mn increased egg production and mass, and decreased FCR, especially at the supplemental level of 40 mg/kg. • Inorganic and organic Mn quadratically increased tibial characteristics and fecal Mn excretion, and organic Mn being more effective. • The 40 ~ 80 mg/kg Mn (inorganic) or 20 mg/kg Mn (organic) would be appropriate for laying ducks (45–64 wk) with 30.6 mg/kg basal Mn. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of selenium (Se) supplementation in maternal and offspring diets on performance and antioxidant capacity of ducklings aged from 0 to 2 wk. A total of 144 female Longyan duck breeders aged 22-wk were allotted into 2 treatments and fed a control diet or a 0.16 mg Se/kg supplemented diet. At 40-wk, 120 offspring from each treatment were divided into 2 groups, with 6 replicates of 10 birds. Using a 2 × 2 factorial design, ducklings from each maternal dietary treatment were assigned to a control diet or a 0.16 mg Se/kg supplemented diet from hatch to 2-wk. Compared with Se-deficient diet, maternal diet supplemented with 0.16 mg Se/kg increased the BW of hatchlings (P < 0.01). There were interactions between maternal and progeny diet with 0.16 mg Se/kg in BW of ducklings aged 2 wk and BW gain (BWG) as ducklings from maternal Se/progeny none treatment had the lightest BW and BWG (P < 0.01). Maternal diet with 0.16 mg Se/kg decreased plasma concentration of uric acid and insulin-like growth factor 1 (P < 0.01), and progeny diet supplemented with 0.16 mg Se/kg increased the activities of glutathione peroxidase 3 (GPx3) in plasma and glutathione peroxidase 1 in erythrocyte (P < 0.01). Maternal diet with 0.16 mg Se/kg increased (P < 0.05) the hepatic activity of total superoxide dismutase (T-SOD). Progeny diet supplemented with 0.16 mg Se/kg increased (P < 0.01) hepatic activity of GPx3 and decreased (P < 0.01) the hepatic concentration of malondialdehyde. Interactions were detected between maternal and progeny diet with 0.16 mg Se/kg in hepatic activity of T-SOD and maternal and progeny diet supplemented with Se displayed the highest hepatic activity of T-SOD (P < 0.05). Overall, Se supplementation in the diet of duck breeders and offspring increased the antioxidant capacity of ducklings. Maternal Se supplementation increased the BW of hatchlings, whereas maternal and progeny dietary Se supplementation did not affect the BWG of ducklings aged from 0 to 2 wk. Se supplementation with additional 0.16 mg/kg in the diet of duck breeders and offspring displayed beneficial effects particularly on the antioxidant capacity in ducklings. [ABSTRACT FROM AUTHOR]

This study was aimed at studying use of reduced dietary crude protein (CP) level supplemented with additional amino acids in laying ducks. A total of 720 Jingjiang ducks (50 wk) were randomly assigned to 5 treatments and fed 5 basal diets with CP levels at 17.5, 16.5, 15.5, 14.5, or 13.5%, with additional amino acids added to each diet for 12 wk. Each treatment had 6 replicates of 24 ducks each. Dietary CP levels affected (P < 0.05) egg production and mass of laying ducks, and there was a linear and quadratic decrease with decreasing CP levels (P < 0.05). Dietary CP levels did not affect egg weight and feed conversion ratio (FCR), but egg weight decreased linearly (P < 0.05); FCR increased linearly and quadratically (P < 0.05) with decreasing CP levels. There were no significant differences in egg quality among the different CP levels (P > 0.05). Ovarian weight, total and mean weight of preovulatory follicles, and total weight of small yellow follicles (SYF) were decreased by dietary CP levels (linear, P < 0.01 and quadratic, P < 0.05). The oviductal weight decreased linearly (P < 0.05), and the number of SYF decreased linearly and quadratically with decreasing CP levels (P < 0.05). The serum estradiol content decreased linearly with dietary CP levels (P < 0.05). The serum contents of luteinizing hormone, prolactin, and progesterone decreased (P < 0.05), linearly and quadratically (both P < 0.01) with decreasing CP levels. The serum contents of creatinine (CRE), triglycerides (TG), total cholesterol (TC), and alanine aminotransferase (ALT) activity were affected (P < 0.05) by different dietary CP levels. The total protein content increased linearly (P < 0.05), TC content increased quadratically (P < 0.05), and contents of albumin, CRE, TG, and phosphorus, and activities of aspartate aminotransferase and ALT increased linearly and quadratically (both P < 0.05) with decreasing CP levels. Overall, reduced dietary CP levels with addition of amino acids affected the laying performance, the development of reproductive organs and ovarian follicles, serum hormones, and biochemical indices of laying ducks. Dietary CP levels can be reduced to 14.5% with additional amino acid supplementation for 12 wk in laying ducks without negative effect on laying performance and egg quality. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate the effects of dietary addition of capsaicin (CAP) on egg production performance, follicular development, and ovarian antioxidant capacity in laying ducks. Three hundred seventy eight 58-wk-old laying ducks were randomly divided into 3 treatments, each treatment consisted 6 replicates, with 12 individually caged laying ducks per replicate. Ducks fed a basal diet served as control, the other 2 groups of ducks were fed the same diet containing 150 mg/kg CAP but in the manner of feed restriction (pair-fed) or ad libitum fed. The experiment lasted for 8 wk. The results showed that the dietary supplementation with CAP under conditions of ad libitum feeding increased feed intake (P < 0.001) and tended (P < 0.1) to increase egg production and egg weight in laying ducks but had no effects on daily egg mass and feed conversion ratio. The relative weight of large yellow follicles from the 2 CAP-supplemented groups at 64 wk of age were significantly higher than that of the controls (P = 0.01). The relative weight of the small yellow follicles in the CAP free-fed group was significantly higher than that of the other 2 groups (P < 0.01). Capsaicin supplementation under ad libitum feding conditions tended to increase the number of dominant follicles in laying ducks (P = 0.06). The ovarian mRNA expression of genes related to calcium signaling (TRPV4 , ATP2A2 , ITPR1 , and CaM) in the CAP ad libitum fed groups were significantly higher than those of the other 2 groups (P < 0.05). The ovarian mRNA expression of CDK1 in CAP free-fed ducks was significantly higher than that of the other 2 groups (P = 0.01). Capsaicin supplementation significantly increased the plasma glutathione peroxidase activity (P < 0.01) in comparison with the control group but reduced the malondialdehyde content in the ovaries of laying ducks (P < 0.01). The results of this study indicates that dietary supplementation of CAP increased feed intake and improved egg production performance probably by activating calcium signaling pathway and improving redox status. [ABSTRACT FROM AUTHOR]

Investigates the electroabsorption and saturation behavior of InGaAsP/InP/InAlAs multiple superlattice optical modulators. Use of metalorganic vapor phase epitaxy; Factors influencing structure growth; Exhibition of extremely low leakage current densities.