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Background Anaemia is prevalent in children. Therefore, this study examined the association between dietary patterns and anaemia among children in central South China. Methods Cross-sectional studies were conducted in Mayang, central South China, in 2015 and 2018. Diet data were collected using a questionnaire, and dietary patterns were identified via exploratory factor analysis. Haemoglobin was measured to assess anaemia status. Associations between dietary patterns and anaemia were assessed using a logistic regression model. Results The mean age of the infants surveyed was 14.06 months in 2015 and 16.58 months in 2018. Four dietary patterns were identified among infants aged 6–23 months: a diversified diet consisting mainly of tubers, dairy products, beans and bean products; a traditional diet consisting mainly of cereals, water, soup, vegetables and fruit; mainly breast milk, with a little powdered formula; or mainly multi-nutrient powders. The prevalence of anaemia in infants decreased from 29.49% in 2015 to 20.26% in 2018.In infants fed a diversified diet or multi-nutrient powders with top-quartile (Q4) scores, the risk of anaemia was reduced by 45%(adjusted odds ratio [AOR] = 0.55, 95%CI0.30–0.99, P = 0.047) or 59% (AOR = 0.41, 95% CI0.22–0.78, P = 0.006), respectively, compared to infants in the lowest quartile (Q1). Infants fed mainly breast milk had a 3.26-fold greater risk of anaemia compared to those with Q1 scores (AOR = 3.26, 95% CI 1.83–5.81, P Conclusions Four dietary patterns were identified among infants aged 6–23 months in central South China. Infants should be fed a variety of food groups to improve their anaemia status.

Backgroud: Anemia is widely prevalent among children, and this study aims to understand dietary patterns and its’ association with anemia.Methods: A cross-sectional design in two time period was conducted at Mayang in 2015 and in 2018. The diet data was collected by questionnaire, and dietary patterns were identified by exploratory factor analysis. Hemoglobin (Hb) was measured to assess the status of anemia. The association between the dietary patterns and anemia was assessed by the logistic regression model.Results: The mean age of infants were 14.06 months in 2015 and 16.58 months in 2018. Four dietary patterns were identified among infants aged 6-23 months in central-south China. Diversified pattern: mainly tubers, dairy products, bean and bean products; traditional pattern:mainly cereals, water and soup, and other vegetables and fruits; breast milk pattern: mainly breast milk but less powered formulas; and multi-nutrient powders pattern: mainly multi-nutrient powders. The prevalence of anemia among infant reduced from 29.49% in 2015 to 20.26% in 2018. The top quartile (Q4) of diversified pattern and multi-nutrient powders pattern deminished the risk of anemia by 45% (OR = 0.55, 95% CI: 0.30 to 0.99, P = 0.047) and 59% (OR = 0.41,95% CI: 0.22 to 0.78, P = 0.006) compared to the lowest quartile (Q1), while the breast milk pattern had a 3.26-fold greater risk of anemia than the lowest quartile (Q1) (OR = 3.26,95%CI:1.83 to 5.81, P Conclusions: Four dietary patterns were identified among infants aged 6-23 months in central-south China. The pattern with a variety of food groups should be strengthened to improve anemia among infants.

Assuming in the perfectly competitive market, using the optimal control theory and making the social welfare as the maximization target, the paper studies on environment control which impacts the optimal extraction path of exhaustible resource. The special case result shows that: reserve and the changes of environment capacity function and curve are influenced by original reserve, discounted value, the absolute ratio of green environment flow to resource extraction quantity, and marginal cost.

Based on the characteristics of natural gas demand trend, this paper proposed ARIMA model which can predict China's natural gas demand as an effective tool. Compared with the RBF neural network model and combined model, empirical results show that the accuracy and stability of the ARIMA model is best.

Energy demand system is a complex system, which is affected and controlled by many factors and external environmental in its development and evolution process. This paper selected the prediction method of correlation, in the way of literature review at first, preliminary qualitatively choose factors which influence the energy demand. Then the direct, indirect and total effect degree of each factor on energy demand were measured by the method of path analysis. On the basis of path analysis, used ridge regression to eliminate multicollinearity to forecast China's energy demand, the prediction accuracy is high, and its practicability in this model is good.

With the rapid development of coal mining rights market, case-based evaluation method will become more and more important in coal mining rights evaluation in the future. Currently case-based mining right evaluation methods home and abroad don’t solve the key problems like the criterion of case selecting, the set-up of similarity model. Based on case-based reasoning and the theories and methods of modern statistics, this thesis reveals the basic principle of case-based evaluation method of coal resource mining right, defines the important concepts like attribute index, attribute strength function, underlying asset, case assets, and case similarity; then establishes case selecting criterions and similarity model under the condition that attribute strength function is unknown; finally builds case-based evaluation model of coal resource mining right and its process. Through a practical case of coal mining rights, do researches on the application of this model. The results indicate that the price got from using case-based coal mining rights evaluation method is very close to the final deal price, and that case-based evaluation method is more effective and direct and needs less data than other evaluation methods with the precondition of existence of certain amount of comparable exchange targets.

Since mining rights of coal resources(for short MRCR) could be regarded as a multi-stage compound real option, the evaluation for MRCR can be better solved using op- tion theory than the NPV. In the former research, we developed a two-factor model of evaluating MRCR when the coal spot price and convenience yield are stochastic based on option theory. On the basis of this two-factor model, we set up a three-factor model of evaluating MRCR when the interest rate followed a stochastic process. Through a real example application, we found the model can get higher values than the two-factor model and the NPV. This is because considering the volatility of interest rate can improve the executive opportunity of MRCR.

Coal resources development projects have many characteristics of large investment, irreversibility, long cycle and uncertainty and so on, due to the inherent defects of the traditional NPV method, which can’t effectively deal with the uncertainty faced by the coal resources development investment, thus, the real value of the coal development investment projects are hardly assessed scientifically and rationally. Using the real options method, the paper builds a evaluation model on coal resources development investment project. The results show that using the model to assess the project value of coal resources development investment will be more scientific and rational, parameter analysis leads to the result that interest rates and convenience yields have a negative effect on the critical investment value of the projects, and the high jump frequency will reduce the critical investment value of the projects, while positive changes on jump range can increase.

Problems of collusion and collusion-proof equilibrium on the quality management system certification (QMSC) market in China are discussed in this paper. Firstly, three situations of producing collusion on QMSC market are given. The behavior and its harms of collusion are analyzed from four aspects. Then the intrinsic mechanism of collusion-formed is opened out by building a three-player principal-agent model of CNCA, certification bodies and enterprises. By the model, the game mechanism of forming collusion-proof equilibrium on QMSC market is given. Based on the model analysis, this paper gives four pieces of advice to prevent collusion: (1) to increase the expectation value of punishing collusion behaviors; (2) to decrease the expectation payoff in the condition of collusion; (3) to increase the expected payoff of certificating for certification bodies with good faith; (4) enterprises have nonparticipation with collusion. Finally, four conclusions are given out