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Aims: The objectives of the study were to analyze the relationship between decomposition rates and initial chemistry of leaf litter and to establish an optimal model to predict the decomposition rates of a large number of plant species in karst forests of China. Methods: We determined the decomposition rate of leaf litter from 21 representative species in karst forests through a litterbag experiment. Using Akaike information criteria, we selected an optimal model among 925 regression models of decomposition rate based on initial chemistry indexes to estimate annual leaf-litter-decomposition rate for an additional 96 important species. Results: Of the 21 representative species, Elaeocarpus decipiens and Phoebe sheareri exhibited the highest (62.85 %) and lowest (23.50 %) annual decomposition rates, respectively. In the first and second quarters, climatic conditions were not advantageous to decomposition, but 20 species reached their highest decomposition rate. Most of 117 tested species accumulated fewer nutrients and more non-easily-decomposed materials in their leaf litter than plant species in non-karst forests. The selected optimal model was: $$ \mathrm{annual} \ \mathrm{decomposition} \ \mathrm{rate}=111.838-0.114\;\left( {\mathrm{total} \ \mathrm{carbon}} \right)+0.021\;\left( {\mathrm{total} \ \mathrm{nitrogen}} \right)+0.068\;\left( {\mathrm{total} \ \mathrm{potassium}} \right)-0.027\;\left( {\mathrm{lignin}} \right)-0.398\;\left( {\mathrm{tannin}} \right)-0.015\;\left( {\mathrm{starch}} \right) $$. Predicted annual leaf-litter-decomposition rates of the additional 96 tree species were 20-80 %. Conclusions: This study enhances our understanding of leaf-litter decomposition for plant species in karst forests and provides a method for estimating annual leaf-litter-decomposition rates. [ABSTRACT FROM AUTHOR]

In large cohort studies it can be impractical to report individual data that only summary or aggregated data are available. Using aggregated data from Bernoulli trials is expected to result in overdispersion so that a quasi-binomial approach would seem feasible. We show that when applied to aggregated data arising from cohorts of individuals according to a chain binomial model, the quasi-binomial model results in biased estimates. We propose an alternate calibration estimator and demonstrate its improved performance by simulations. The calibration method is then applied to model the probability of leaving a personal emergency link service in Hong Kong. [ABSTRACT FROM AUTHOR]

Abstract: Eight models using only the sunshine duration for estimating the global solar radiation on a horizontal surface are evaluated at Changdu, Geer, Lasa and Naqu stations in Tibet, China against the measured meteorological data during 1994–2008. Based on statistical error tests, results show that the simple linear Ångström–Prescott model is reasonably accurate in practice, and the modifications with complex expression are not necessary in Tibet. Then, two general Ångström–Prescott models for estimating the daily and monthly average daily global solar radiation respectively in Tibet are proposed. [Copyright &y& Elsevier]

Abstract: Reliable and accurate determinations of the quantities and composition of wastes is required for the planning of municipal solid waste (MSW) management systems. A model, based on the interrelationships of expenditure on consumer goods, time distribution, daily activities, residents groups, and waste generation, was developed and employed to estimate MSW generation by different activities and resident groups in Beijing. The principle is that MSW is produced by consumption of consumer goods by residents in their daily activities: ‘Maintenance’ (meeting the basic needs of food, housing and personal care), ‘Subsistence’ (providing the financial requirements) and ‘Leisure’ (social and recreational pursuits) activities. Three series of important parameters – waste generation per unit of consumer expenditure, consumer expenditure distribution to activities in unit time, and time assignment to activities by different resident groups – were determined using a statistical analysis, a sampling survey and the Analytic Hierarchy Process, respectively. Data for analysis were obtained from the Beijing Statistical Yearbook (2004–2008) and questionnaire survey. The results reveal that ‘Maintenance’ activity produced the most MSW, distantly followed by ‘Leisure’ and ‘Subsistence’ activities. In 2008, in descending order of MSW generation the different resident groups were floating population, non-civil servants, retired people, civil servants, college students (including both undergraduates and graduates), primary and secondary students, and preschoolers. The new estimation model, which was successful in fitting waste generation by different activities and resident groups over the investigated years, was amenable to MSW prediction. [Copyright &y& Elsevier]

Abstract: Measurements of surface radiation in China are too sparse to meet demand for scientific research and engineering applications. Moreover, the radiation data often include erroneous and questionable values though preliminary quality-check has been done before the data release. Therefore, quality control of radiation data is often a prerequisite for using these data. In this study, a set of quality-check procedures were implemented to control the quality of the solar radiation measurements at 97 stations in China. A hybrid model for estimating global solar radiation was then evaluated against the controlled data. The results show that the model can estimate the global radiation with accuracy of MBE less than 1.5MJm−2 and RMSE less than 2.8MJm−2 for daily radiation and RMSE less than 2.0MJm−2 for monthly-mean daily radiation at individual stations over most of China except at a few stations where unsatisfactory estimates were possibly caused by severe air pollution or too dense clouds. The MBE averaged over all stations are about 0.7MJm−2 and RMSE about 2.0MJm−2 for daily radiation and RMSE about 1.3MJm−2 for monthly-mean daily radiation. Finally, this model was used to fill data gaps and to expand solar radiation data set using routine meteorological station data in China. This data set would substantially contribute to some radiation-related scientific studies and engineering applications in China. [Copyright &y& Elsevier]

Abstract: In this paper, in contrast to the usual rough estimation, we present a model to simulate and evaluate the direct, indirect economic and environmental impacts of the implementation of building energy efficiency standards on Chinese economic system and environment by 12 indicators in two scenarios. Four indicators are used to evaluate the direct economic impact degree, five indicators are used to evaluate the direct environmental impact degree, three indicators are used to evaluate the indirect economic impact degree of 34 sectors and the whole Chinese economic system. This research makes it possible to link developments in the implementation of building energy efficiency standards with environmental and economic structure change. The most important finding is that the implementation of building energy efficiency standards can reduce a large amount of pollutants emissions and increase the GDP at the same time. [Copyright &y& Elsevier]

In this paper a failure model of the mixed Inverse Weibull distributions(MIWD) is considered and its estimators for all unknown parameters based on type-II and type-I censored data are obtained by means of EM-Algorithm. Some simulations suggest that EM algorithm is effective to our model. [ABSTRACT FROM AUTHOR]