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A feeding trial was conducted to evaluate the efficacy of dietary heat-killed Lactobacillus plantarum L-137 (HK L-137) on growth performance, digestive, non-specific immune and phagocytosis of sea cucumber, Apostichopus japonicus. Sea cucumbers (initial body weight 1.35 AE 0.04 g) were fed diets supplemented with five levels of HK L-137 (0, 0.005, 0.025, 0.05 and 0.25 g HK L-137 kg À1 diets) for 60 days. Results indicated sea cucumbers fed with diets containing 0.05 and 0.25 g HK L-137 kg À1 diets showed significantly (P < 0.05) higher body weight gain and specific growth rate than other groups. Sea cucumbers fed with diets containing 0.05 and 0.25 g HK L-137 kg À1 diets showed significantly (P < 0.05) higher protease activity than control group. Higher amylase, lysozyme and phagocytic activities were found in 0.25 g HK L-137 kg À1 diet group. Higher superoxide dismutase enzyme and alkaline phosphatase activity was found in 0.05 g HK L-137 kg À1 . While no significant differences (P > 0.05) were found in acid phosphatase activity. These results suggested that dietary supplementation of 0.05 g HK L-137 kg À1 diets would have benefit on growth, digestive enzymes and several non-specific immune parameters of sea cucumber.

With respect to decision making problems under uncertainty, a trapezoidal intuitionistic fuzzy multiattribute decision making method based on cumulative prospect theory and Dempster-Shafer theory is developed. The proposed method reflects behavioral characteristics of decision makers, information fuzziness under uncertainty, and uncertain attribute weight information. Firstly, distance measurement and comparison rule of trapezoidal intuitionistic fuzzy numbers are used to derive value function under trapezoidal intuitionistic fuzzy environment. Secondly, the value function and decision weight function are used to calculate prospect values of attributes for each alternative. Then considering uncertain attribute weight information, Dempster-Shafer theory is used to aggregate prospect values for each alternative, and overall prospect values are obtained and thus the alternatives are sorted consequently. Finally, an illustrative example shows the feasibility of the proposed method. theory-based decision making method than an expected utility theory-based decision making method.Recently, some scholars have incorporated prospect theory into multiattribute decision making. Bleichrodt et al.[5] studied the multiattribute utility under prospect theory, but there was no direct link between utilities and choices, and they did not provide data correlation process for the prescriptive analysis. In order to solve this problem, Gomes and Lima [6] proposed a method called TODIM which was a discrete MADM method used to solve riskless decision problems based on prospect theory, but its inability to deal with uncertainty and imprecision decision information affected its application. Then some scholars have considered the uncertainty and imprecision decision information, Wang and Sun [7] proposed a fuzzy multiple criteria decision making method based on prospect theory; Lahdelma and Salminen [8] introduced the SMAA-P method that combined the piecewise linear difference functions of prospect theory with SMAA; Liu et al. [9] researched the multiattribute

The performance-based payment PPP model has been widely used in the infrastructure projects. However, the ratchet effect derived from performance-based reputation incentives has been largely overlooked. To overcome this shortcoming, ratchet effect is considered in the performance-based payment incentive process. A multi-period dynamic incentive mechanism is developed by coupling the reputation and ratchet effect. The main results show that: (1) Under the coupling of reputation and ratchet effects, the optimal incentive coefficient in the last performance assessment period is always greater than that of the first period. The bargaining power can replace part of the incentive effect; (2) Due to the ratchet effect, if the government improve performance targets through performance adjustment coefficients, it needs to increase incentives to overcome the decreasing effort of the private sector; (3) When the bargaining power and punishment coefficient are small, the reputation incentive is replacing the explicit incentive. The increasing incentive coefficient would make the ratchet effect dominant the reputation effect; (4) To prevent the incentive incompatibility derived from the ratchet effect, the government should increase the incentive while increasing the punishment to achieve the “penalties and rewards”. This study provides theoretical and methodological guidance to design incentive contracts for infrastructure PPP projects.

The stable isotopic study of the mechanism of runoff replenishment in the Qinghai-Tibet Plateau is a time-consuming and complicated process requiring complex monitoring data and scientific evaluation methods. Based on the data of water stable isotopes (18O and 2H) in the Naqu River basin, the present paper developed a framework of the variable fuzzy evaluation model (VFEM) to provide a method to classify stable isotopes and generalize the source identification of water replenishment by rainfall or snowmelt in the Naqu River basin. The grade eigenvalues of tributaries were ranked from low to high as follows: 1, 1.005, 1.089, 1.151, 1.264, 1.455 and 2.624. Three sets of tributaries were distinguished. The grade eigenvalues of the Najinqu, Bazongqu, Mumuqu, Chengqu and Gongqu Rivers were small, indicating that these tributaries were strongly supplemented by precipitation and snowmelt; the grade eigenvalue of the Zongqingqu River was in the medium range (1.455); the third group included the Mugequ River with a high status value (2.624). This study mainly highlighted the combination of the classification of stable isotopes and plots of δ2H vs. δ18O in the source identification of water replenishment, which will be helpful for studying runoff replenishment and the evolution mechanism in the Qinghai-Tibet Plateau.

Sediment gradually accumulates at the bottom of reservoirs after decades of running. To explore the influences of sediments on the water quality of reservoirs, the spatial distribution, adsorption/release characteristics, and environment influence of sediment pollutants should be analyzed. In this paper, the spatial distributions of phosphorus (P) and P fractions in the Biliuhe reservoir (river valley reservoirs) sediments were investigated. The adsorption and release characteristics of sediments P were studied in the experiment, while its environmental influence was analyzed too. The results indicate that the concentration of P in sediments was higher at the dam and the Zhongling site, while lower at other entrances of the reservoir and the smallest in the water-level fluctuating zone. Total Phosphorus (TP) varied from 355.46 to 764.57 mg/kg. Inorganic Phosphorus (IP) was the main form of TP in sediments, making up a proportion of 56-75%, while the correlation coefficient of P bound to Al, Fe, and Mn oxides was 0.922. Hydroxide (Fe/Al-P) was the main form of IP, which accounted for 46-83% with a correlation coefficient of 0.888. The maximum adsorption capacity calculated by Langmuir model was between 714.29 and 3333.33 mg/kg. The adsorption efficiency obtained by the Freundlich model was within the range of 0.40-1.42, which indicated that P adsorption was more difficult in the water-level fluctuating zone. The critical adsorption and release concentration range was 0.1-0.2 mg/L for the majority of the sampling points. The amount of P released in 24 h (the initial concentration of TP in the overlying water was 0 mg/L) accounted for 1.15-4.16% of TP in sediments, which was higher than the average concentration in the reservoir. It is concluded that the sediment is the potential pollution source. The relationship between the change of environmental factors and the release of sediment contaminants should be considered in the future.

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The reheat steam temperature control system of thermal power unit is a complex control object with time-varying parameters and large delay. In order to achieve precise control of reheat steam temperature, the performance of the reheat temperature control system is analyzed according to the data that are obtained based on the constrained predictive control algorithm. Firstly, the process and mathematical model of reheat steam temperature control system are introduced. Then the principle of constrained predictive control algorithm is analyzed. Finally, the steady-state values of control quantities of reheat steam temperature control system under different conditions are given by MATLAB simulation, and, by analyzing the steady-state values and steady-state time of the input and output of the system, the reference values and the regulating law of the control quantities and the specific constraint range of the control quantities of the system are given, which can provide reference data and theoretical basis for the field adjustment of the reheat steam temperature control system in power plant and improve the safety and effectiveness of the system.