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To systematically and thoroughly analyze the sensitivity and reliability of the MSBAS regularization for the estimation of surface deformation over a mine in combination with an application example, this study processed 101 Sentinel-1A/B SAR images, constructed and solved the 2D deformation models using SVD and Tikhonov regularization methods with different orders and parameters, and estimated the vertical and east-west surface deformation time series in a mine of China. Then, this study collected the leveling-monitoring vertical surface deformation data on three leveling points, and compared and analyzed the sensitivity and reliability of the MSBAS regularization methods for estimating vertical surface deformation. The results indicate that different regularization orders and parameters can lead to thousands of times differences in condition numbers and significant differences in illposed degree of the deformation models. The zero-order Tikhonov regularized deformation model with regularization parameter of 0.1 has the minimum condition number and the equation is not ill-posed. The first-order Tikhonov regularized deformation model with regularization parameter of 0.001 has the maximum condition number and the equation is seriously illposed. As a result, the estimates of 2D surface deformation models with different parameters and orders are also different in terms of numerical values and accuracy. Compared with the leveling-monitoring data, the first- and second-order MSBAS regularization methods with parameter 0.1 have the minimum fluctuation and the maximum correlation coefficients between the estimated values and the leveling-monitoring values, and are also closest to the leveling-monitoring results with the highest accuracy. [ABSTRACT FROM AUTHOR]

It is essential to effectively identify the sources and health risks of heavy metals in groundwater in rural areas. Therefore, the sources and health risks of heavy metals in groundwater in rural areas of Huaibei Plain were investigated. The results showed that the mean concentrations of Cr, Fe, Mn, Cu, Zn, Ni, As, Cd, and Pb were 0.38, 86.48, 90.94, 0.20, 0.97, 1.18, 0.009 and 0.16 μg/L. Multivariate statistical analysis combined with positive matrix factorization (PMF) was used to quantitatively identify four sources (agricultural activities (24.01%), industrial activities (22.27%), natural sources (26.45%), and traffic sources (27.28%)). The probabilistic health risk assessment results based on Monte Carlo simulation showed that the non-carcinogenic risk for adults and children was negligible. However, 17.52% of children and 1.99% of adults exceeded the maximum acceptable safety limit (1.0E-6) for cancer risk. Sensitivity analysis showed that daily intake, Cr, and Fe were the main factors influencing the health risk assessment results. These results have important implications for groundwater management in rural areas of the Huaibei Plain. [ABSTRACT FROM AUTHOR]

In reservoir flood control operation, candidate reservoir operation alternatives are evaluated, ranked and selected by a multi-criteria decision making (MCDM) method. However, deterministic methods cannot handle MCDM problems where uncertainties exist in both criteria performance values (PVs) and criteria weights (CWs). To solve the issue, a SMAA-VIKOR model integrating stochastic multicriteria acceptability analysis (SMAA) theory with the Viekriterijumsko Kompromisno Rangiranje (VIKOR) method is established based on Aydogan and Ozmen (2017). Moreover, we conduct a comprehensive evaluation of the model's decision making results, including risk assessment and sensitivity analysis. The case study applied to a flood control system in Dadu River in China indicates that the SMAA-VIKOR model can quickly identify the optimal alternative that meets the subjective preferences of decision makers, and has remarkable advantages compared to the traditional SMAA-2 model and the deterministic VIKOR method, which can provide theoretical support for making a robust reservoir release decision. [ABSTRACT FROM AUTHOR]

Building silt storage dams is an important measure to control soil erosion. Sensitivity analysis of the parameters in a deep learning model is the premise of extracting high-precision silt storage dams from high-resolution remote sensing (RS) images. In this study, watershed features of Hulu River and Lanni River in the Loess Plateau, China, are extracted using a geographic information system and digital elevation model. The detection of silt storage dams using the U-Net model considered three high-resolution RS image datasets to evaluate the effect of different input sizes, batch sizes, and sample sizes on accuracies of silt storage dams. The results show that a large input size, batch size, and sample size can improve the accuracy of silt storage dams extracted by U-Net. U-Net with Dataset 3, input size of 576 × 576, and batch size of 4 achieved an overall accuracy of 96.26%, F1 score of 70.61%, mean intersection over union of 75.33%, training time of 485 ms/step, minimum noises and shadow, and clear outlines of silt storage dams. This study provides theoretical and practical decision-making for the planning, construction, and maintenance of silt storage dams, as well as ecological protection and high-quality development of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

Cities are pivotal hubs of socioeconomic activities, and consumption in cities contributes to global environmental pressures. Compiling city-level multi-regional input-output (MRIO) tables is challenging due to the scarcity of city-level data. Here we propose an entropy-based framework to construct city-level MRIO tables. We demonstrate the new construction method and present an analysis of the carbon footprint of cities in China's Hebei province. A sensitivity analysis is conducted by introducing a weight reflecting the heterogeneity between city and province data, as an important source of uncertainty is the degree to which cities and provinces have an identical ratio of intermediate demand to total demand. We compare consumption-based emissions generated from the new MRIO to results of the MRIO based on individual city input-output tables. The findings reveal a large discrepancy in consumption-based emissions between the two MRIO tables but this is due to conflicting benchmark data used in the two tables. [ABSTRACT FROM AUTHOR]

Based on elastoplastic and damage mechanics theory, a new theoretical model of damage cracking on the cover of reinforced concrete structures caused by nonuniform rust expansion is established. The parameter sensitivity analysis indicates that the critical corrosion rate of the structure increases sharply with the increase of the thickness of the concrete cover. The critical corrosion rate decreases when the non-uniform coefficient of the corrosion expansion becomes larger, indicating that the uneven corrosion expansion is disadvantageous for durability. When the rust expands more unevenly, the allowable corrosion amount of the reinforcement becomes smaller. While the concrete grade changes from C15 to C60(concrete design standard in China), the critical corrosion rate modifies between 3.05°C and 4.1°C. To further verify the rationality of the new theoretical model, the model was conducted to predict the standard corrosion tests. Results show that the scatter points predicted by the new model are small-amplitude oscillation near the test line. Thus, it has been proved the new theoretical model proposed in this paper can be used to predict the critical corrosion rate of RC structures. [ABSTRACT FROM AUTHOR]

This paper explores the design approach of multi-atrium configurations to improve the energy efficiency of shopping malls in cold climates. A typical building prototype in northern China was considered, and an artificial neural network (ANN)-based metamodel was developed with four design variables: the atrium area ratio (r), atrium number (n), distance between adjacent atriums (d0), and distance between atrium and façade wall (d1). The proposed metamodel was used for sensitivity analysis (SA) and building design optimization (BDO) to understand the performance of multi-atrium configuration. The SA indicates that the contribution of the design variables to the building energy efficiency follows the order r > d0 > n > d1, and there are interactions between variables r and n. The BDO demonstrates that it is beneficial for energy efficiency to incorporate more atrium areas, appropriate atrium sizes, larger distances between adjacent atriums, and more west-facing atriums. [ABSTRACT FROM AUTHOR]

Wellbore pressure distribution is the basis of formation pressure prediction and productivity evaluation. Two gas–liquid two-phase flow models with assumption of constant mass and variable mass rate within production layer are established to predict the wellbore pressure during multilayer commingled production, respectively. Model validation shows that the calculation errors of the models meet the requirement of engineering precision. Sensitivity analysis shows that the overall sensitivity of thick-layers pure gas wells to model parameters is higher than that of thin-layer low water-producing gas wells. In addition, the pay zone 1 to pay zone n of the n-layer combined gas production well can be equivalent to a thick pay zone. With the production of gas wells, the wellbore pressure decreases and the gas holdup rate decreases, and the calculation error of wo-phase flow model with the constant mass flow rate in the production zone is significant. As a result, the model with variable mass rate should be adopted during this situation. The proposed analytical models for the first time, to the best of the authors' knowledge, can accurately calculate the pressure distribution of the wellbore for low water-producing gas well, commonly encountered in tight sandstone gas reservoir (e.g., Ordos basin, China). [ABSTRACT FROM AUTHOR]

Studies have shown that sexual transmission, both heterosexually and homosexually, is one of the main ways of HBV infection. Based on this fact, we propose a mathematical model to study the sexual transmission of HBV among adults by classifying adults into men and women and considering both same-sex and opposite-sex transmissions of HBV in adults. Firstly, we calculate the basic reproduction number R 0 and the disease-free equilibrium point E 0 . Secondly, by analysing the sensitivity of R 0 in terms of model parameters, we find that the infection rate among people who have same-sex partners, the frequency of homosexual contact and the immunity rate of adults play important roles in the transmission of HBV. Moreover, we use our model to fit the reported data in China and forecast the trend of hepatitis B. Our results demonstrate that popularizing the basic knowledge of HBV among residents, advocating healthy and reasonable sexual life style, reducing the number of adult carriers, and increasing the immunization rate of adults are effective measures to prevent and control hepatitis B. [ABSTRACT FROM AUTHOR]

Current housing unit design focuses on performance optimization, such as building energy use, daylighting, and occupant comfort. There is significant potential for efficient optimization in the early design stage. This paper proposed a building energy demand optimization framework that considers building design variables for housing unit design in Beijing. First, a high-rise apartment building was designed using geometric and thermal envelope parameters. Second, a thermal load simulation of the housing unit was performed. Third, sensitivity analysis and multi-objective optimization were conducted to evaluate the building's performance. Finally, a neural network was trained to predict the thermal load. A comparison of the base case and optimal cases revealed that more than 20% of energy demand could be saved. In addition, the effect of the parameters on the thermal load and the lighting schedules on the unit's energy load were analyzed. [ABSTRACT FROM AUTHOR]

Aiming at the inconsistent design standards of China's high-speed railway, the effect of wheel structure on friction-induced wheel polygonal wear is studied. A finite element model is established that consists of two rails, one wheelset, and three brake units. The motion stability of the system is studied through complex eigenvalue analysis. According to the mode analysis, the unstable vibration induced by the disc brake may be the cause of wheel polygonal wear. Furthermore, the parameter sensitivity analysis shows that the web plate shape has a significant effect on suppressing the wheel polygonal wear. Moreover, the sensitivity of the system with different wheel web plate–to–wheel diameter values differs. When the value of the wheel diameter increases from 860 to 920 mm in the wheel–rail–disc brake system with an oblique web plate, the effective damping ratio of unstable vibration changes significantly. In addition, the occurrence of polygonal wear increases with an increase in the tread wear depth. [ABSTRACT FROM AUTHOR]

China has set an ambitious target of achieving the grid parity of solar power by 2020 in the 13th Five-Year Plan. This paper estimates the levelized costs of electricity (LCOE) of centralized photovoltaic power across regions in China with the actual situation in 2016 and simulation scenarios for 2020. Results demonstrate that the LCOEs of centralized photovoltaic power will decrease considerably during the period of 13th Five-Year. Few of them are competitive with generation side electric prices in 2016 basic scenario and 2020 pessimistic situation. Sensitivity analysis reveals that utilization hour, unit investment cost, and financing cost are key driving factors. [ABSTRACT FROM AUTHOR]

This study evaluates housing price control policies in China between 2006 and 2016. A panel regression is employed to diagnose the explicit effects of these policies on housing supply and demand, followed by a nonstationary Markov model and t-copula to assess the policy sensitivity of the real-estate sector and the banking sector. This paper presents two important discoveries. First, total social welfare, represented by the sector fundamentals, is extremely sensitive to even tiny shocks from policy adjustments. Second, the current policies effectively restrain the supply of housing but not housing demand. As a result, the current policies fail to achieve their intended outcome by, on the one hand, driving up housing prices with a declining supply of housing and stable demand and, on the other, harming total social welfare. The empirical economic conditions in China are consistent with our findings. [ABSTRACT FROM AUTHOR]

To assess the health risks caused by soil heavy metal in China's mining areas, concentration data for eight heavy metals in 77 mines were collected from previous literature. Monte Carlo simulation was used to analyze the corresponding carcinogenic risks and noncarcinogenic risks, and sensitivity analysis was carried out for each parameter. The results showed that among the different types of mining areas, multi-metal mines have the highest risk of carcinogenesis, followed by tungsten and antimony mines. Their carcinogenic risk values are all greater than 10−4, which is unacceptable. Pb is a heavy metal with highest noncarcinogenic risk. The log-transformed value is 3.2, which is much larger than the threshold of 0; Pb is followed by As and Hg. Therefore, Pb, As, and Hg are the heavy metals that should be controlled preferentially in polluted mining areas. Sensitivity analysis showed that the soil ingestion rate, exposure frequency, and pollutant concentration level are the factors that have the greatest impacts on health risks. More attention should be paid to these factors when addressing heavy metal pollution in mining areas. In addition, for the surveyed mines, children had a greater health risk than adults, so children should be given extra attention. [ABSTRACT FROM AUTHOR]

This paper uses slope, distance,visual probability and remarkableness as evaluation indices to study urban landscape visual sensitivity in the Zhongshan District of Dalian. The results show that areas of high sensitivity account for 14.12% of the total area, these areas should be protected. Moderate sensitivity areas occupy 2.66%, urban landscape transformation should be carried out properly. Low-sensitivity areas accounted for only 0.74%, the utilization of vegetation and the construction of public facilities can be carried out in these areas. Areas classified as insensitive account for 82.48%, this is a potential zone where the urban landscape can be developed. [ABSTRACT FROM AUTHOR]

To investigate the effect of drag force on stability of residual soil slopes, a modified approach based on the limit equilibrium method is proposed by establishing a nonlinear coupled mathematical model to calculate the seepage velocities in soils and the runoff velocities at a fluid-solid interface. In this mathematical model, the Navier-Stokes equation and Brinkman-extended Darcy equation are used to describe the incompressible surface runoff and seepage in soils, respectively. Then, the drag force can be derived by adopting Newton's law of internal friction, and the factor of safety (FOS) of residual soil slopes considering drag force can be calculated based on the limit equilibrium method. The modified approach was applied to analyse the stability of rainfall-induced landslides in residual soils in Nanjiang, Sichuan, China, 2011. We found that the runoff depth can significantly control the FOS of the residual soil slopes and cause slope failures. The results of sensitivity analysis highlight the significance for considering drag force due to surface runoff when calculating the FOS of the residual soil slope. The FOS obtained from the modified approach is more reasonable, and this modified approach also can be used for evaluating or predicting rainfall-induced slope instability in residual soils. [ABSTRACT FROM AUTHOR]

Parameter calibration and sensitivity analysis (SA) are usually not straightforward tasks for distributed hydrological models, owing to the complexity of models and the large number of parameters. A two-step SA approach is proposed for analysing hydrological signatures based on the distributed hydrology–soil–vegetation model (DHSVM) in the Jinhua River Basin, East China. A preliminary SA is conducted to obtain influential parameters via analysis of variance. These parameters are further analysed through a variance-based global sensitivity analysis method to achieve robust rankings and parameter contributions. Parallel computing is designed to reduce the computational burden. The results reveal that only a few parameters are significantly sensitive and that interactions between parameters cannot be ignored. When analysing hydrological signatures, it is found that water yield is simulated very well for most samples. Small and medium floods are simulated very well, while slight underestimations happen for large floods. [ABSTRACT FROM AUTHOR]

Artificial neural networks are sophisticated modelling and prediction tools capable of extracting complex, non-linear relationships between predictor (input) and predicted (output) variables. This study explores this capacity by modelling non-linearities in the hardiness-modulated burnout process with a neural network. Specifically, two multi-layer feed-forward artificial neural networks are concatenated in an attempt to model the composite non-linear burnout process. Sensitivity analysis, a Monte Carlo–based global simulation technique, is then utilised to examine the first-order effects of the predictor variables on the burnout sub-dimensions and consequences. Results show that (1) this concatenated artificial neural network approach is feasible to model the burnout process, (2) sensitivity analysis is a prolific method to study the relative importance of predictor variables and (3) the relationships among variables involved in the development of burnout and its consequences are to different degrees non-linear. Practitioner Summary: Many relationships among variables (e.g. stressors and strains) are not linear, yet researchers use linear methods such as Pearson correlation or linear regression to analyse these relationships. Artificial neural network analysis is an innovative method to analyse non-linear relationships and in combination with sensitivity analysis superior to linear methods. [ABSTRACT FROM AUTHOR]

The authors analyze the sensitivities of source regions in East Asia to PM2.5(particulate matter with an aerodynamic diameter of ≤2.5 µm) concentration at Fukue Island located in the western part of Japan by using a regional chemical transport model with emission sensitivity simulations for the year 2010. The temporal variations in PM2.5concentration are generally reproduced, but the absolute concentration is underestimated by the model. Chemical composition of PM2.5in the model is compared with filter sampling data in spring; simulated sulfate, ammonium, and elemental carbon are consistent with observations, but mass concentration of particulate organic matters is underestimated. The relative contribution from each source region shows the seasonal variation, especially in summer. The contribution from central north China (105°E–124°E, 34°N–42°N) accounts for 50–60% of PM2.5at Fukue Island except in summer; it significantly decreases in summer (18%). Central south China (105°E–123°E, 26°N–34°N) has the relative contribution of 15–30%. The contribution from the Korean Peninsula is estimated at about 10% except in summer. The domestic contribution accounts for about 7% in spring and autumn and increases to 19% in summer. We also estimate the relative contribution to daily average concentration in high PM2.5days (>35 μg m−3). Central north China has a significant contribution of 60–70% except in summer. The relative contribution from central south China is estimated at 46% in summer and about 30% in the other seasons. The contributions from central north and south China on high PM2.5days are generally larger than those of their seasonal mean contributions. The domestic contribution is smaller than the seasonal mean value in every season; it is less than 10% even in summer. These model results suggest that foreign anthropogenic sources have a substantial impact on attainment of the atmospheric environmental standard of Japan at Fukue Island.Implications: The contribution from several source regions in East Asia to PM2.5 concentration at Fukue Island, a remote island located in the western part of Japan and close to the Asian continent, is estimated using a three-dimensional chemical transport model. The model results suggest that PM2.5 that is attributed to foreign anthropogenic sources have a larger contribution than that of domestic pollution and have a substantial impact on attainment of the atmospheric environmental standard of Japan at Fukue Island. [ABSTRACT FROM AUTHOR]

In this paper, we describe our polarimetric interferometric synthetic aperture radar (PolInSAR) experiments with high-resolution X-band data acquired by a multi-mode airborne SAR system over an area of Linshui in southern China. First, we introduce our latest multi-mode X-band airborne imaging radar system (Multi-Mode-XSAR), which integrates three operation modes of bistatic, ping-pong, and mixed. Then, the Multi-Mode-XSAR data set and the corresponding ground measurements in test areas are briefly described. Considering the characteristics of the Multi-Mode-XSAR imagery, a dual-baseline polarimetric interferometry (DPI) method is proposed in this article. The proposed method guarantees a high coherence on the full polarimetric data and combines the benefits of short and long baselines to facilitate the phase unwrapping and promote height sensitivity. Our PolInSAR experiment results demonstrate that the DPI method is capable of generating DSM with higher accuracy than other multi-baseline (MB) methods and the Multi-Mode-XSAR imagery has great potential in PolInSAR applications. [ABSTRACT FROM AUTHOR]

Phenology event responses, based on vegetation types, are strong indicators of climate variability and the ability of the vegetation to adapt to future climate changes. However, the sensitivity of phenology events to climate change along either environmental or vegetation type gradients is rarely examined. Phenological curves of major vegetation types along the North−South Transect of Eastern China (NSTEC) have been developed using wavelet and smooth-spline methods based on the normalized difference vegetation index from 1982 to 2006. Spatial−temporal patterns, trends of greenup-onset dates, dormancy dates, and growing season lengths (GSLs) during the period of 1982−2006 are presented. The greenup-onset dates were most significantly and negatively related to the temperature in cold and humid areas, but insignificantly and positively in semi-arid regions. However, dormancy date showed a positive correlation with temperature. In populations of the same vegetation type, distributed along thermal gradients of NSTEC, the phenology sensitivities to warming were different. Greenup sensitivities of cold temperate coniferous forest (CTCF) and temperate meadow steppe (TMS) increased significantly from −6.0 to 0 days °C−1(p < 0.001) and from about −2.0 to 2.0 days °C−1(p < 0.001), respectively. In contrast, temperate grass steppe (TGS) and temperate deciduous shrubland (TDS) showed a decreased trend of greenup sensitivity from 2.0 to −4.0 days °C−1(p < 0.001) and from 2.0 to −6.0 days °C−1(p < 0.001), respectively. For the dormancy date sensitivity, CTCF showed a decreasing trend from about 6.0 to 0 days °C−1(p < 0.001), and subtropical evergreen-broadleaved forest (SEBF) decreased from 5.0 to −5.0 days °C−1(p < 0.05). [ABSTRACT FROM PUBLISHER]

Objective. To evaluate the predictive values of the leukocyte parameters for hypertensive disorders in pregnancy (HDP). Methods. A total of 523 HDP patients and 853 normal pregnancies were included in the present study. The leukocyte parameters in different stages of pregnancy were compared among the groups, and the efficiency of clinical diagnosis was calculated to analyze the predictive value of these parameters to HDP. Results. Women with HDP presented significantly higher leukocyte parameters in the second trimester and significantly lower values in the last trimester as compared to the normal gravidas. An evident increase of several parameters was observed preceding the clinical syndromes of HDP; and the odds ratio of increased neutrophil (NEU) and basophil (Baso) for predicting HDP were 1.02 and 1.16 ( p < 0.01), respectively. The sensitivity of NEU was 71.95%% when it was higher than 6.12 × 109//L, and the specificity of Baso was 71.01%% when it was higher than 0.053 × 109//L for the prediction of HDP in 13-20 weeks. Conclusion. The NEU and Baso are helpful for predicting HDP during the presymptom period. [ABSTRACT FROM AUTHOR]

To explore the spatial and temporal variations of the reference evapotranspiration (ETref) is helpful to understand the response of hydrological processes to climate changes. In this study, ETref was calculated by the Penman-Monteith method (P-M method) using air temperature, wind speed, relative humidity and sunshine hours at 89 meteorological stations during 1961-2006 in the Yellow River Basin (YRB), China. The spatial distribution and temporal variations of ETref were explored by means of the kriging method, the Mann-Kendall (M-K) method and the linear regression model, and the causes for the variations discussed. The contribution of main meteorological variables to the variations of ETref was explored. From the results we found that: (1) the spatial distributions of ETref display seasonal variation, with similar spatial patterns in spring, summer and autumn; (2) temporal trends for ETref showed large variation in the upper, middle and lower regions of the basin, most of the significant trends (P = 0.05) were detected in the middle and lower regions, and, in particular, the upward and downward trends were mainly detected in the middle region and lower region of the basin, respectively; and (3) sensitivity analysis identified the most sensitive variable for ETref as relative humidity, followed by air temperature, sunshine hours and wind speed at the basin scale. Citation Yang, Zhifeng, Liu, Qiang & Cui, Baoshan (2011) Spatial distribution and temporal variation of reference evapotranspiration during 1961-2006 in the Yellow River Basin, China. Hydrol. Sci. J. 56(6), 1015-1026. [ABSTRACT FROM AUTHOR]

It is difficult to analyse soil properties quantitatively with multispectral remote sensing data. An alternative solution is to determine the main spectral characteristic control points of soil hyperspectral reflectance curves by sensitivity analysis methods. Hyperspectral reflectance is simulated using the control points based on multispectral reflectance collected from satellites in this study. The laboratory hyperspectral reflectance and its continuum-removed curve of Phaeozem and the parent material (PM) of samples collected from Heilongjiang Province, China were analysed, and the spectral characteristic control points determined. Hyperspectral simulating linear and quadratic models based on laboratory reflectance were then built. Results show that montmorillonite and illite are the dominant minerals in Phaeozem PM. Organic matter content determines the spectral characteristics of Phaeozem and makes it suitable for reflectance simulation in the spectrum range of 1000 nm and less; the higher the organic matter content the greater the spectral absorption area. There are two absorption valleys at 500 and 660 nm, which determine the spectral characteristic control points of Phaeozem between 450 and 930 nm, namely 450, 500, 590, 660 and 930 nm. Both the linear and quadratic simulation models built with the characteristic control points accurately describe Phaeozem reflectance, which proves that the characteristic control points are selected reasonably and representatively. The hyperspectral simulation method based on multispectral reflectance closely represents the characteristics of Phaeozem hyperspectral reflectance, partly removes noise and improves the precision of predicting organic matter content. Therefore the method is feasible and useful for data compression of Phaeozem hyperspectral reflectance, soil and vegetation indices building, and quantitative remote sensing in the Phaeozem Zone, northeast China. [ABSTRACT FROM AUTHOR]

Environmental flows represent the quality, quantity and timing of water flows required to sustain the benefits provided to human, plant and animal communities by a healthy freshwater ecosystem. The precise characteristics of environmental flows can be difficult to define, however, and the precise impact of changes in these flows on the ecosystem service value (ESV) is likewise difficult to quantify. Using China's Baiyangdian Lake as a case study, I evaluated the ecosystem services provided by the lake from 1980 to 2005. The results showed that ESV was influenced by changes in the lake's environmental flows from its tributaries and revealed the potential relationship between ESV and water elevation. The ESV depended significantly on water elevation; thus, water elevation can be used as a proxy for changes in ESV and can provide guidance for effective environmental management. A sensitivity analysis revealed that the total ESV estimate for the study area was relatively inelastic based on changes in the coefficient of sensitivity (CS), and that the estimation was therefore robust. These results demonstrate that the relationship between ESV and water elevation is sufficiently strong and robust to help managers allocate water to balance the lake's environmental flows and ESV. [ABSTRACT FROM PUBLISHER]

In this article, we give a coupled system model of differential equations concerning pressure and temperature in high-temperature-high-pressure wells according to mass, momentum, and energy balances. We present an algorithm solution model, along with the fourth-order Runge-Kutta method. The basic data for the X Well (a high-temperature-high-pressure gas well, 6,115 m deep) in China were used for case history calculations and a sensitivity analysis was made for the model. In curve graphs, gas pressure and temperature along the depth of the well were plotted with different gradients, intuitively reflecting the gas flow law and characteristics of heat transfer in formation. The results can provide technical reliability in the processing of well test design in high-temperature-high-pressure gas wells and the dynamic analysis of production. [ABSTRACT FROM AUTHOR]

Efficient planning and design of an appropriate reverse logistics network is crucial to the economical collection and disposal of scrapped household appliances and electrical products. Such systems are commonly modelled as mixed-integer programs, whose solutions will determine the location of individual facilities that optimize material flow. One of the major drawbacks of current models is that they do not adequately address the important issue of uncertainty in demand and supply. Another deficiency in current models is that they are restricted to a two-echelon system. This study addresses these deficiencies by embodying such uncertainties in the model using the technique of fuzzy-chance constrained programming, and by extending the model to a three-echelon system. A heuristic in the form of a hybrid genetic algorithm is then employed to generate lowcost solutions. The overall objective is to find economical solutions to the general problem of determining the volume of appliances to be moved between the three echelons of customer base to collection sites, collection sites to disposal centres and disposal centre to landfill centre/remanufacturing centre; and to the problems of positioning the disposal centres and the landfill centre/remanufacturing centres within the problem domain. A case example in China is presented and the quality and robustness of the solutions are explored through sensitivity analysis. . [ABSTRACT FROM AUTHOR]

Using panel data analyses, this paper examines the relation between human capital formation and Foreign Direct Investment (FDI) in China. It shows that FDI has a significant effect on human capital formation, at least for the period 1995-2001. When we estimate the relationship between FDI and skill formation for the coastal and non-coastal provinces separately, the positive relationship is maintained, and this relationship also holds when we consider investment in real estate or the ratio of number of foreign firms to total number of firms investing in China. The results stand robust in the causality test and the sensitivity analysis. [ABSTRACT FROM AUTHOR]

This article develops a systems dynamics and multi-objective programming model (SDMOP) for planning a regional circular economy. Various risk analyses are conducted using the technique of sensitivity analysis. This SDMOP model includes two modules: the MOP module used to derive optimized parameters as inputs to the systems dynamics model, and the systems dynamics module used to plan the regional circular economy. We demonstrate the application of this SDMOP model to a problem of planning the circular economy of a county in the Sichuan Province of China. [ABSTRACT FROM AUTHOR]