Abstract: This paper proposes a maglev device for a vertical hydro-turbine to replace the thrust-bearing. The structure of the device is given. For the given mechanical structure, a design and optimization method is put forward and the process is provided. The dimension parameters are optimized to make the best use of material for bigger force density and better control performance. The ideal common linear model is built and the nonlinear programming method is used to decide the primary size parameters. The results are inaccurate tested by finite element analysis (FEA) because the model is rough. A more accurate reluctance network (RN)…model is set up and the PSO method is applied to get the optimal point. The results from the two models are compared. The feasibility and validity of the latter method is verified.
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Keywords: Maglev device, dimension, optimization, reluctance network, force density
Abstract: Due to different knowledge background and language habit, decision makers generally provide multi-granularity unbalanced linguistic terms to assess possible alternatives in linguistic decision situation. In this paper, a new linguistic term transformation method is proposed to transform multi-granularity unbalanced linguistic terms into 2-tuple linguistic values of any fixed linguistic term set. The new method consists of transformation of linguistic term and 2-tuple linguistic representation of transformation, the aim of transformation of linguistic term is to obtain a unified information of multi-granularity unbalanced linguistic term based on its triangle membership function, 2-tuple linguistic representation of transformation is to transform the unified…information as 2-tuple linguistic values of any fixed linguistic hierarchy. A practical decision making problem is utilized to illustrate the practicality of the new method, more important, it is compared with existing important transformation methods in the practical decision making problem, the result shows that the new method is an alternative method to transform multi-granularity unbalanced linguistic term sets.
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Keywords: Linguistic decision making, Multi-granularity unbalanced linguistic terms, 2-tuple linguistic model, linguistic aggregation operator
Abstract: This paper proposes an improved Markov Chain Monte Carlo (MCMC) estimation method. First, it introduces improved Markov Chain Monte Carlo estimation method, then uses extended Kalman filter to approximate the nonlinear transfer equation, and ultimately completes the estimation of the redefined asymmetric SV model combining with the forward filtering and backward sampling algorithm. The experimental results indicate that the new algorithm has a faster convergence rate. Finally, this improved MCMC method of asymmetric SV model is applied to the liquidity management of commercial banks. The fitting results not only illustrate its efficiency and accuracy, but also show the empirical evidence…of leverage effect.
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Abstract: The potential feedback by intracellular nitrogen pools on maximum N uptake (NH_4^+) rate were determined for Gracilaria tenuistipitata var. liui and Ulva pertusa. The results of correlation matrix analyzing showed that the surge uptake of ammonium seemed related to rapid changes in small intracellular pools of inorganic nitrogen or small peptide and amino acids rather than to changes in TN content of the macroalgae. The assimilation rates of nitrogen of U. pertusa and G. tenuistipitata increased slowly during N starvation and were mainly regulated by amino acids and some incorporation of amino acids into macromolecules. From ecological point of view,…the fast-growing and uptaking nutrient U. pertusa is more suitable to improve water quality in integrated shrimp culture ponds in which external nutrient supplies are usually high and constant during the culture period, while G. tenuistipitata var. liui is more suitable to be polycultured in a waters with intermittence supply of nutrients.
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Abstract: This paper deals with the N storage of Gracilaria tenuistipitata var. liui and Ulva pertusa under ammonium enrichment and starvation. After 10 days of ammonium enrichment, ammonium NH_4^+, free amino acid (FAA), protein (pro), chlorophyll (Chl),phycoerythrin (PE) and total dissolved nitrogen (TDN) of the two macroalgae increased significantly. Total nitrogen (TN) increased significantly from 3.65% to 5.78% dry weight of G. tenuistipitata var. liui and 2.82% to 5.07% dw of U. pertusa, respectively. Protein and FAA were the most important N storage pools in the macroalgae. During N-starvation period, individual N pools of the two species were depleted at exponential…rates. Each N pool in U. pertusa decreased more rapidly than in G. tenuistipitata, var. liui and the latter was able to sustain fast growth for more time (> 20 days) than U. pertusa. N demands for supporting growth were different between the two species,U. pertusa grew more rapidly and had higher N demands than G. tenuistipitata var. liui did.
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Abstract: Element cycling in the dominant plant communities including Rh. aureum, Rh. redowskianum and Vaccinium uliginosum in the Alpine tundra zone of Changbai Mountains in northeast China was studied. The results indicate that the amount of elements from litter decomposition was less than that of the plant uptake from soil, but that from plant uptake was higher than that in soil with mineralization process released. On the other hand, in the open system including precipitation input and soil leaching output, because of great number of elements from precipitation into the open system, the element cycling (except N, P) in the Alpine…tundra ecosystem was in a dynamic balance. In this study, it was also found that different organ of plants had significant difference in accumulating elements. Ca, Mg, P and N were accumulated more obviously in leaves, while Fe was in roots. The degree of concentration of elements in different tissues of the same organ of the plants also was different, a higher concentration of Ca, Mg, P and N in mesophyll than in nerve but Fe was in a reversed order. The phenomenon indicates (1) a variety of biochemical functions of different elements, (2) the elements in mesophyll were with a shorter turnover period than those in nerve or fibre, but higher utilization rate for plant. Therefore, this study implies the significance of keeping element dynamic balance in the alpine tundra ecosystem of Changbai Mountains.
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Abstract: The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe-Luanhe Basin of North China was analyzed. The calculating method of the ecological and environmental water demand of the lake basis on the water body and the calculating method of the ecological and environmental water demand of the lake basis on the aquatic ecosystem, wetland and vegetation were compared and discussed. As the examples of Baiyangdian Lake and Beidagang Lake in Haihe-Luanhe river basin, the ecological and environmental…water demand of the two lakes was calculated to be 27 × 10^8m³ . It is 6.75 times to the water demand according to the calculating method of the ecological and environmental water demand of the lake basis on the water body. The research result indicated: ( 1 ) The calculating methods of the ecological and environmental water demand of the lake basis on the aquatic ecosystem should be better than only basis on the water body of lake. (2) The data, such as area of the vegetation kind around and in the lake, the vegetation coefficient, the evaporating amount of the vegetation and the vegetation water demand itself around and in the lake are lack and urgent need. Some suggestions for controlling and regulating the water resource of the lake in North China were proposed.
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Keywords: eco-environment, water demand, lake, the Haihe-Luanhe Basin
Abstract: In general, many pollutants co-exist in natural aquatic ecosystems. They affect each other and occur different results, such as synergism, addition and antagonism. So the research at mixtoxicity of contaminants to aquatic organism is more important than monotoxicity. In this paper, 50% effectual inhibition concentration 48h EC_50 values of 6 kinds of nitroaromatic compounds to the green algae, Scenedesmus obliquus, were investigated. Mixtoxic experiments, in which any combination of 2,4-DNT and other 6kinds of compounds, indicate: (1) synergisms between 2,4-DNT and 4-NAn, as well as 4-NAnis, 1,4-DNB; (2) antagonisms between 2,4-DNT and 4-NT, as well as 4-NPh, 4-NCB.
Keywords: monotoxicity, mixtoxicity, nitroaromatics, green algae
Abstract: This paper presents a canonical duality theory for general box constrained nonconvex and nonsmooth optimization problems. The theory is illustrated perfectly by showing mainly a canonical dual transformation and a triality theory. It is proved that the general box constrained nonconvex and nonsmooth optimization problems can be changed into the perfect dual problems, which can be solved easily. The perfect dual transformation is developed for eliminating the duality gap,while the triality theorem studies global and local extreme conditions. Applications and examples are illustrated.
Keywords: Canonical (perfect) dual transformation, triality theory, box constrains, nonconvex and nonsmooth minimization, global and local optimization
Abstract: In this study, it was investigated whether a NO signaling pathway is involved in the anti-epileptic effect of curcumin on pentylenetetrazol (PTZ)-kindled rats. PTZ-kindled rats received different doses of curcumin that were administered intraperitoneally for 24 days. Either a non-selective inhibitor of nitric oxide synthase (NOS) (N-nitro-L-arginine methyl ester (L-NAME)), a selective inhibitor of neuronal NOS (7-Nitroindazole (7-NI)), a selective inhibitor of inducible NOS (aminoguanidine (AG)), or a NO precursor (L-arginine (L-ARG)) was administered chronically to evaluate the role of NO in curcumin’s anti-seizure effect. A chronic administration of curcumin (200 mg/kg) was most effective for decreasing the mean frequency…of epileptiform discharge. Furthermore, a pretreatment with L-NAME or 7-NI augmented the anti-epileptic effect of curcumin. In contrast, AG failed to significantly alter the anti-epileptic effect of curcumin. A pretreatment with L-ARG temporally reversed the anti-epileptic effect of curcumin in the early stage, but in the late stage, it potentiated curcumin’s anti-epileptic effect. These findings suggest that the L-arginine–nitric oxide pathway may be involved in the anti-epileptic properties of curcumin, and that the role of nNOS (and not iNOS) is prominent in this neuroprotective feature.
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