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This paper describes the performance of the Regional Atmospheric Modeling System (RAMS) in simulating a winter drought event, based on two different forcing datasets. We ran EC (ERA-Interim reanalysis data as initial and lateral boundary forcing conditions) and FNL (NCEP-FNL reanalysis data) simulations for the 2008/2009 winter drought event to quantify the impact of any uncertainty in the different initial and lateral boundary forcing data on regional model outputs. The response of the winter mean atmospheric states to the variations in the initial and lateral boundary conditions was investigated on the basis of these simulation results. The spatio-temporal features of precipitation from the EC and FNL runs closely resembled those measured from the Global Summary Of the Day (GSOD) observations, although the EC run data outperformed the FNL run data in both their spatial distribution patterns and precipitation values. The water vapor flux values explain how the differences in the precipitation values between the EC and the FNL runs were generated, whereas temperature values were not sensitive to any changes in forcing data. The model results from these runs also slightly overestimated temperature on both spatial and temporal scales. For the tropospheric atmospheric data recorded at the Fuyang Meteorological Station in Anhui Province, neither the time series nor the statistical analyses showed any evidence of superiority between the two different driver datasets compared with radiosonde data. However, on closer inspection, the influence of different initial and lateral boundary conditions on modeling the tropospheric atmospheric data appeared to be evident. [ABSTRACT FROM AUTHOR]

Purpose – Scheduling needs to be concise and well-determined but able to respond to the ever-changing and uncertain market or environment against the constraints of production capacity, resources, time frame, etc. The purpose of this paper is to model and solve a scheduling problem with another domain perspective that adopts the concept of agent, and an agent-based scheduling environment is proposed for solving the scheduling problem, in which three agents are developed, i.e. a sales agent, a scheduling agent, and a production agent. Design/methodology/approach – The modeling and development of the proposed agent-based scheduling environment and its agents under constraints are discussed. Constraint priority scheduling concepts are applied to the environment and its agents, and the feature of responding to customer change orders is included in the model. The proposed agent-based scheduling environment with three agents is applied to a lamp-manufacturing company in China as a case study, and the integrated agent-based approach is also illustrated in the case study. Findings – Throughout the autonomous communication between agents in the proposed model, a constraint-prioritized schedule is generated to fulfill customer orders and customer change orders, as well as to achieve a better scheduling performance result. From the simulation results and analysis in the case study, satisfactory results show that the proposed model can generate a constraint-prioritized schedule for the studied company that can completely fulfill customer orders, adjust and fulfill customer change orders, and achieve a better scheduling result. Originality/value – In this paper, the scheduling problem is modeled and solved by using the domain perspective of agent-based approach. By using an agent-based approach, the agents can be implemented to represent manufacturing resources or aggregations of resources. Under the proposed modeling approach, the collaboration across the entire scheduling activities can be enhanced, and the efficiency and effectiveness in the scheduling activities can also be increased. [ABSTRACT FROM AUTHOR]

This paper presents a rapid forecast model for simulating hyperconcentrated sediment-laden floods in the Lower Yellow River. The model is a hybrid of a conventional one-dimensional mathematical model for unsteady sediment-laden flow and an artificial neural networks model for encapsulation of numerical results. The former provides detailed river flood routing information under typical scenarios, whereas the latter extracts modeling outputs from the former and establishes a station-specific model for efficient flood forecasting. Three typical floods that occurred in the Lower Yellow River in 1977, 1982, and 1996 are simulated. Not only the hybrid model predictions are found to be in close agreement with measured data, but also the computational speed is significantly enhanced. It is found that sediment transport is of significance with regard to the flooding behavior of hyperconcentrated flows. Therefore, the model presented herein is of particular use for rivers with high sediment concentration. [ABSTRACT FROM AUTHOR]

Abstract: Snow cover is a common and relatively stable land cover condition in winter for cold north regions in China. Snow cover has significant effects on water and heat transfers in frozen soil; it needs to be considered in the study of frozen soil water–heat coupled movements. On the basis of previous research results and physical process analysis of water and heat movements in snow cover and soil, a snow cover–soil union water–heat coupled movements model is established in this paper. The numerical simulation was conducted by using a finite difference method. The results indicate that the simulated values have a similar trend to the measured values and the numerical simulation had big relative errors. However, the average absolute errors of the total and liquid moisture content in frozen soil were all less than 4%, and that of the frozen soil temperature was 1.37 °C. The errors of the numerical simulation were still within the acceptable range. Thus, the snow cover–soil union water–heat coupled movement model constructed in this paper is rational. [Copyright &y& Elsevier]

Summary: The rapid economic development has caused heavy pollution in the Pearl River Delta Region (PRDR) and neighboring regions. In order to investigate the polluted characteristics, a coupled modelling approach has been deployed and the study area in the Pear River Delta is divided into two modelling systems: a river network that is simulated by a 1D hydrodynamic and water quality model, and an estuary that is modelled by a 3D model. The 1D river network model is coupled with the 3D estuary model based on the mass conservation criteria. The hydrodynamic (HD) model is based on 1D hydrostatic shallow water equations, and is solved by the Alternating Direction Implicit Approach. The water quality (WQ) model component is based on advection–diffusion equations. Some physical and bio-chemical processes are included in the WQ model to address the water pollution problems by different pollution substances, in particular, to the chemical oxygen demand (COD). The water quality data of the main rivers from 2004 to 2007 were collected, processed and evaluated. Because no detailed water quality data in the river is available, the COD source pollution intensity in the water quality model is taking the pollutant load from the confluence of the main five outlets of the Pearl River Estuary (PRE) for 1996–2007 as surrogate. The results show that the pollutants from the PRDR have a large impact on the quality of the Hong Kong seawater and much more serious in the wet season with high river discharge. An insight of the flow and transportation mechanism in the river and estuary system has been obtained through the paper, and a reliable basis to control water pollution of the Pearl River Delta is provided in this paper. [Copyright &y& Elsevier]

Abstract: With the start up of West–East Natural Gas Transmission Project, the construction of natural gas-pipeline will enter on a new era in China. The development tendency will be towards large-diameter, high-pressure and long-distance for natural gas-pipelines. Correspondingly, the life cycle cost of natural gas-pipeline networks is increasing gradually. The mainline system is a vital part of natural gas network systems. The investment required for the mainline system is enormous, usually accounting for 80% of the total investment for this system. In general, the investment required for a gas-pipeline depends on its operating parameters. Therefore, based on the characteristics of gas networks, optimization for investment becomes indispensable to gas networks design. A comprehensive and optimal mathematic model of a gas networks system is established in this paper which considers all the factors influencing the total investment of a gas networks system (e.g. pipe diameter, thickness, pressure, length, compression ratio, etc). From the standpoint of the characteristics of a model comprising both continuous and discrete variables, a new methodology, rank-optimization, is presented. On the basis of this model, a simple and visual high-pressure networks optimization program has been compiled. Furthermore, the developed optimization program has been applied to a practical project and the effects of operating parameters on the total investment have been analyzed. The simulation model in this paper is shown to be an effective method to solve optimization on mainline system in high-pressure gas networks. [Copyright &y& Elsevier]

This paper reviews various sources of literature on the languages of the She minority. Previous scholarship can generally be divided into three aspects: those that study the genetic affiliation of the She language (Sheyu); those that study the relation between the She speech (Shehua) and Chinese dialects, or between Shehua and Zhuang-Dong languages; and those that study languages of the She people as an endangered language. The paper points out the future development of She research, which will aim at safeguarding languages of the She minority. The status of Sheyu and Shehua and their interrelationship will be better clarified when studies proceed with the perspective of basic core vocabulary. Furthermore, studies on languages of the She minority require interdisciplinary methodologies that combine language competition and mathematical modeling to explore factors contributing to the endangerment of She people's languages. [ABSTRACT FROM AUTHOR]

Based on a public building in China, this paper built a benchmark model and analyzed the influence of main thermal performance of building envelopes on energy consumption in different climatic regions by EnergyPlus. The results showed that in the order of hot summer and warm winter region, hot summer and cold winter region, cold region, severe cold region, the energy-saving effect was getting better and better with the increase of roof insulation, exterior wall insulation and exterior window insulation. If SHGC of exterior window was reduced, building energy consumption decreased in hot summer and warm winter region, hot summer and cold winter region, but it increased in cold region and severe cold region. For hot summer and warm winter region, hot summer and cold winter region, the factors that affected energy consumption was as follows: SHGC > K win > K wal > K ro, for cold region and severe cold region, it was as follows: K win > K wal > SHGC > K ro . [ABSTRACT FROM AUTHOR]

In recent years, Beijing rural “coal to electricity” is more and more attention. Among them, the air source heat pump as a clean energy is vigorously promoted, but due to of its low water supply temperature. So, for what kind of terminal equipment need to be researched. In this paper, the two terminal equipment of PE-X pipe are adopted as the low-temperature floor radiant heating and four-post 760 cast iron radiator in the bedroom of a Beijing farmhouse are simulated. The performance of two kinds of terminal equipment is analyzed from four aspects: indoor temperature field distribution, indoor air cleanliness, indoor air velocity distribution and energy consumption. The commercial CFD software was used to simulate the characteristics of two heating terminal equipment. The simulation results show that PE-X pipes as the low-temperature floor radiant heating is better than that the four-post 760 cast iron radiator heating, it has good heating effect. [ABSTRACT FROM AUTHOR]

Planetary rovers may traverse terrains with complex geometries and variable physical properties, but their mobility behaviors are complicated and difficult to simulate precisely. This article focuses on high-fidelity dynamic modeling and simulation for a type of rovers that incorporate single-input-multi-output joints to enhance terrain adaptability, which has been used on China's Tianwen-1 Mars rover. A novel multibody dynamic model and its solutions are derived first with consideration of single-input-multi-output joints. Then, a unified terramechanics model is proposed, considering variable terrain surfaces and covering rover's motion states of skidding, slipping, and steering, solved the problem of simulation instability caused by model switching between soft and hard terrains. As the contact areas of wheels with various terrains and resultant sinkage are dominant factors to ensure fidelity but difficult to determine, a new terrain modeling method for calculating contact area and wheel sinkage is developed using digital elevation map with physical properties. A simulation system is developed, integrating all the above models, and verified with physical experiments and commercial software. The relative simulation errors that have been achieved are less than 5.9% for bogie angles, 6.1% for drawbar pull, and 3.4% for slip ratios, demonstrating high fidelity simulation results. [ABSTRACT FROM AUTHOR]

To simulate and analyze a large aircraft with severe wind shear, nonlinear equations for a rigid aircraft under various wind conditions were designed. In this paper, a double-vortex-ring method is adopted to generate a three-dimensional microburst wind field. This model incorporates a flight dynamics module and three flight simulations based on various forms of nonlinear equations. In addition, four primary wind gradients are considered to compute the aerodynamic coefficients. In simulation experiments with a China C series large aircraft, equations using air-relative velocities and inertial velocities are compared and analyzed. Although the nonlinear equations derived using the air-relative velocities should be identical to those using the inertial velocities, the results show that the latter are more accurate in practice because the former bring error into the simulation when estimating the acceleration induced by the wind field. [ABSTRACT FROM AUTHOR]

A dynamic computable general equilibrium model that contains 37 production sectors and 4 foreign accounts was developed in this paper to study the impacts of USA's border carbon adjustments on China's economy. Based on the data of year 2007, 7 scenarios with different tax rates were designed from the year 2020 up to the year 2030. The simulation results show that the USA's border carbon adjustments will cut down Chinese enterprises' profits of export to USA, decrease China's export to USA, and indirectly have negative impacts on the whole economy. The USA's border carbon adjustments will have different impacts on different industries in China, amongst of which the industry of electric power and heat power generation and industry of cement, lime and gypsum may suffer most from the USA's carbon motivated border tax adjustments policy. [ABSTRACT FROM AUTHOR]

Abstract: Carbon Crystal Panel (CCP) system, a new type of electric-heating system material based on the mechanism that nano carbon crystal sends out quantity of heat when it is electrified, enjoys lots of advantages, such as good controllability, cleanness during using, and high thermal response-speed. Compared with experimental data, the validity of mathematical physical model of the indoor CCP system is verified. According to the occupied feature of office rooms in southern cities of China, partial-heating program of CCP system is put forward and its indoor temperature field is simulated. The result shows, under the partial-heating condition, the temperature in localized working region comes up to the indoor designed temperature; the partial-heating program achieves the effect of energy-conservation. This paper provides technical support for the application of CCP system in public buildings. [Copyright &y& Elsevier]

Summary: After the Yangtze River was closed by the Three Gorges Project (TGP) in 2003, erosion occurred from the dam site to the river mouth, especially in the middle and lower reaches of the Yangtze River. However, in some local areas of Chenglingji reach which holds the key position for flood management, there is actually deposition in contrast to the expected erosion. In this paper, a one dimensional mathematical model of the river network with sediment transport is used as the tool to simulate flow and fluvial processes. The calculation domain is from Yichang, which is downstream of the dam, to Hankou, the controlling node of flood management, 694km long in total. The model is calibrated based on the field data of hydrology and sediment transport during the period from October 2003 to October 2008. Then the model is utilized to simulate the erosion and deposition of the middle and lower reaches of the Yangtze River in the next two decades, and produce the results of a new river channel after river bed deformation occurs. The typical flood processes of 1954 and 1998 in the Yangtze River basin are used to check the flood management scheme for the research area, and results show that water storage of Three Gorges Reservoir (TGR) and a flood diversion program downstream of the Yangtze River should be taken into consideration. [Copyright &y& Elsevier]

Abstract: This paper aims to use detailed modelling techniques and develop a database for assessing in a quick and easy way the energy performance of green roof designs across a range of Chinese climates. The focus is on heating and cooling loads by calculating indoor temperatures using the EnergyPlus simulation tool. The study covers 5328 configurations by varying model parameters such as location, climate, seasonal periods, glazing type, wall insulation levels, roof insulation, soil thickness and condition, and vegetation density characteristics. It was found from the results that green roofs can offer significant energy savings for heating and cooling loads if they are applied on roofs without insulation but only limited energy savings where heavy insulation on the roof is also applied. This database can prove to be a useful tool to the practitioners who want to perform rapid assessments of the potential energy savings that could be gained from a green roof installation in a Chinese location. [Copyright &y& Elsevier]

Abstract: Based on gray error GM (1,1) model, the paper proposed an improved error GM (1,1) model, and used this model to predict cultivated land in Yiyang. The results show that the improved error GM (1,1) model has high prediction accuracy, and better simulation results. And the results conform to the cultivated quantity change rule of Yiyang City, that is, the land area of Yiyang City, will appear in the next few years, modest growth trend, but the per capita arable land is still in the alert level of the United Nations. Therefore, protection of cultivated resources, rational utilization and protection of arable land are urgent tasks. [Copyright &y& Elsevier]

Abstract: Techniques for modelling urban microclimates and urban block surfaces temperatures are desired by urban planners and architects for strategic urban designs at the early design stages. This paper introduces a simplified mathematical model for urban simulations (UMsim) including urban surfaces temperatures and microclimates. The nodal network model has been developed by integrating coupled thermal and airflow model. Direct solar radiation, diffuse radiation, reflected radiation, long-wave radiation, heat convection in air and heat transfer in the exterior walls and ground within the complex have been taken into account. The relevant equations have been solved using the finite difference method under the Matlab platform. Comparisons have been conducted between the data produced from the simulation and that from an urban experimental study carried out in a real architectural complex on the campus of Chongqing University, China in July 2005 and January 2006. The results show a satisfactory agreement between the two sets of data. The UMsim can be used to simulate the microclimates, in particular the surface temperatures of urban blocks, therefore it can be used to assess the impact of urban surfaces properties on urban microclimates. The UMsim will be able to produce robust data and images of urban environments for sustainable urban design. [ABSTRACT FROM AUTHOR]

Abstract: As China’ largest oilfield, Daqing is of great importance to China, this paper analyzes the status of the Daqing oilfield and forecasts its ultimate recoverable reserves by use of the URR model. The forecast results are presented for three scenarios which show that the ultimate recoverable reserves in Daqing oilfield are 3574.0million tons in the optimistic scenario, 3169.3million in the base case scenario and 3033.3million in the pessimistic scenario, respectively. A system dynamics model is established and the quantitative relationships between variables in the model are determined. Total oil production, remaining recoverable reserves, annual newly discovered reserves, and the degree of reserves recovery before 2060 are simulated under the three scenarios by use of the system dynamics model. The forecast results show that the future oil production in Daqing oilfield will continue declining, under the base case scenario, from 41.6million tons in 2007 to 8.0million tons in 2060. For Chinese policy-makers, it is worth paying attention to the problem of whether oil production in new oilfields can effectively make up for the decline in production of the large, old oilfields. [Copyright &y& Elsevier]

Abstract: This paper presents a three-dimensional (3-D) numerical model to simulate morphological changes in alluvial channels due to bank erosion. A method for the simulation of bank erosion is established. This is incorporated into a 3-D mathematical model for turbulent flow and non-uniform, non-equilibrium sediment transport. This model is applied to simulate morphological changes in the Shishou bend of the middle Yangtze River in China, where serious bank erosions occurred during the last two decades. The double-layer sediment structure of the riverbank on the middle Yangtze River is taken into account in the bank erosion module. Both cohesive and non-cohesive bank material in the different layers are considered. The bank erosion module also includes other factors affecting the rate of bank erosion, such as the longitudinal length of failed bank, the thickness of each layer in the double-layer structure, and the erosion-resisting effect of cohesive material from the top layer of failed bank. A locally-adaptive grid system is proposed to efficiently simulate the lateral migration of alluvial channel due to bank erosion. The predictive capability of the 3-D model is examined by laboratory data. Simulated processes of bank erosion agree with field observations in the Shishou bend during the period of October 1996–October 1998, and the bank erosion module plays a significant role in simulating morphological changes of the study reach. In addition, the equivalent channel-forming discharge, which is defined as a constant discharge that can create the same amount of bank erosion in an alluvial channel as that created by natural runoff processes during the same period of time, is proposed to improve calculation efficiency for feasibility studies. [Copyright &y& Elsevier]

Abstract: In 1988, Dr. Kyoji Sassa proposed a geotechnical model [Sassa, K., 1988. Geotechnical model for the motion of landslides. In: Proceedings, 5th International Symposium on Landslides, vol. 1, pp. 37–56] to simulate landslide motion and to establish a theoretical framework for landslide simulation. In 2002, based on the experimental results of using a ring-shear apparatus for simulation of landslide motion, Wang and Sassa proposed a model for apparent friction coefficient change (which is a key parameter of landslide motion) that can be combined with Sassa’s original geotechnical model. As presented in the model for apparent friction coefficient change, a landslide is considered as a two-layer structure, i.e., a debris layer and a sliding zone. During landsliding, the thickness of the debris layer changes, while shear resistance changes in the sliding zone. In this paper, after a brief introduction of the two models, a parametric study is presented to show the differing importance of each parameter. Also included is a presentation of three case studies: The 1995 Fei Tsui Road landslide, and the 1995 Shum Wan landslide, both in Hong Kong, and the 1903 Frank slide in Alberta, Canada to show the advantage of combining the two models. [Copyright &y& Elsevier]

This paper describes the development of a land use model coupling ecosystem processes. For a given land use pattern in a region, a built-in regional ecosystem model (TESim) simulates leaf physiology of plants, carbon and nitrogen dynamics, and hydrological processes including runoff generation and run-on re-absorption, as well as runoff-induced soil erosion and carbon and nitrogen loss from ecosystems. The simulation results for a certain period from 1976 to 1999 were then used to support land use decisions and to assess the impacts of land use changes on environment. In the coupling model, the land use type for a land unit was determined by optimization of a weighted suitability derived from expert knowledge about the ecosystem state and site conditions. The model was applied to the temperate crop-pasture band in northern China (CCPB) to analyze the interactions between land use and major ecosystem processes and functions and to indicate the added value of the feedbacks by comparing simulations with and without the coupling and feedbacks between land use module and ecosystem processes. The results indicated that the current land use in CCPB is neither economical nor ecologically judicious. The scenario with feedbacks increased NPP by 46.78gCm−2 a−1, or 32.23% of the scenario without feedbacks, also decreased soil erosion by 0.65kgm−2 a−1, or 23.13%. Without altering the regional land use structure (proportions of each land use type). The system developed in this study potentially benefits both land managers and researchers. [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]

In this research, an integrated simulation-optimization modeling approach (ISOMA) was developed for supporting agricultural N2O emission mitigation at the watershed scale. This approach can successfully combine soil N2O emission simulation and the consequential mitigation management within a general modeling framework. Also, uncertainties associated with the key soil parameter can be effectively reflected and addressed through adoption of Monte Carlo analysis for the simulation results. The Monte Carlo simulated results were then used to generate fuzzy membership functions that can be consequentially used for emission mitigation management, reflecting the combined uncertainties for N2O emission simulation and mitigation management. The developed ISOMA was then applied to a reservoir watershed in Miyun county of Beijing municipality. In the studying watershed, the simulation model was calibrated and verified. Then, N2O emission from multiple agricultural land-use patterns were predicted. The amounts of N2O emission of four land use patterns (i.e., cash tree, orchard, cropland, and natural forest) were (536.9, 590.8, 653.1), (237.7, 254.4, 275.9), (79.5, 100.7, 105.1), (33.0, 47.3, 61.1) kg CO2 eq ha−1 year−1, respectively. Two scenarios (i.e., G1 and G2) were set up according to development priorities of local economy and society. Meanwhile, multiple credibility levels were considered according to the risk of N2O emission. The land use patterns could be adjusted according to solutions of ISOMA. The developed methods could help regional manager choose various production patterns with cost-effective agriculture N2O emission management schemes in the Miyun reservoir watershed. The manager also can obtain deeply insights into the tradeoffs between agricultural benefits and system reliabilities. [ABSTRACT FROM AUTHOR]

Purpose: Urban rail transit is a complex and dynamic system, which is difficult to be described in a global mathematical model for its scale and interaction. In order to analyze the spatial and temporal characteristics of passenger flow distribution and evaluate the effectiveness of transportation strategies, a new and comprehensive method depicted such dynamic system should be given. This study therefore aims at using simulation approach to solve this problem for subway network. Design/methodology/approach: In this thesis a simulation model based on multi-agent approach has been proposed, which is a well suited method to design complex systems. The model includes the specificities of passengers' travelling behaviors and takes into account of interactions between travelers and trains. Findings: Research limitations/implications: We developed an urban rail transit simulation tool for verification of the validity and accuracy of this model, using real passenger flow data of Beijing subway network to take a case study, results show that our simulation tool can be used to analyze the characteristic of passenger flow distribution and evaluate operation strategies well. Practical implications: The main implications of this work are to provide decision support for traffic management, making train operation plan and dispatching measures in emergency. Originality/value: A new and comprehensive method to analyze and evaluate subway network is presented, accuracy and computational efficiency of the model has been confirmed and meet with the actual needs for large-scale network. [ABSTRACT FROM AUTHOR]

Ambient OH and HO2 concentrations were measured by laser induced fluorescence (LIF) during the PRIDEPRD2006 (Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta, 2006) campaign at a rural site downwind of the megacity of Guangzhou in Southern China. The observed OH concentrations reached daily peak values of (15-26) x 106 cm-3 which are among the highest values so far reported for urban and suburban areas. The observed OH shows a consistent high correlation with j(O¹D) over a broad range of NOx conditions. The correlation cannot be reproduced by model simulations, indicating that OH stabilizing processes are missing in current models. The observed OH exhibited a weak dependence on NOx in contrast to model predictions. While modelled and measured OH agree well at NO mixing ratios above 1 ppb, a continuously increasing underprediction of the observed OH is found towards lower NO concentrations, reaching a factor of 8 at 0.02 ppb NO. A dependence of the modelled-to-measured OH ratio on isoprene cannot be concluded from the PRD data. However, the magnitude of the ratio fits into the isoprene dependent trend that was reported from other campaigns in forested regions. Hofzumahaus et al. (2009) proposed an unknown OH recycling process without NO, in order to explain the high OH levels at PRD in the presence of high VOC reactivity and low NO. Taking a recently discovered interference in the LIF measurement of HO2 into account, the need for an additional HO2→OH recycling process persists, but the required source strength may be up to 20% larger than previously determined. Recently postulated isoprene mechanisms by Lelieveld et al. (2008) and Peeters and Müller (2010) lead to significant enhancements of OH expected for PRD, but an underprediction of the observed OH by a factor of two remains at low NO (0.1-0.2 ppb). If the photolysis of hydroperoxy aldehydes from isoprene is as efficient as proposed by Peeters and Müller (2010), the corresponding OH formation at PRD would be more important than the primary OH production from ozone and HONO. While the new isoprene mechanisms need to be confirmed by laboratory experiments, there is probably need for other, so far unidentified chemical processes to explain entirely the high OH levels observed in Southern China. [ABSTRACT FROM AUTHOR]

The 1951-2009 drought history of China is reconstructed using daily soil moisture values generated by the Variable Infiltration Capacity (VIC) land surface macroscale hydrology model. VIC is applied over a grid of 10 458 points with a spatial resolution of 30 km x 30 km, and is driven by observed daily maximum and minimum air temperature and precipitation from 624 long-term meteorological stations. The VIC soil moisture is used to calculate the Soil Moisture Anomaly Percentage Index (SMAPI), which can be used as a measure of the severity of agricultural drought on a global basis. We have developed a SMAPI-based drought identification procedure for practical uses in the identification of both grid point and regional drought events. As a result, a total of 325 regional drought events varying in time and strength are identified from China's nine drought study regions. These drought events can thus be assessed quantitatively at different spatial and temporal scales. The result shows that the severe drought events of 1978, 2000 and 2006 are well reconstructed, which indicates that the SMAPI is capable of identifying the onset of a drought event, its progression, as well as its termination. Spatial and temporal variations of droughts in China's nine drought study regions are studied. Our result shows that on average, up to 30% of the total area of China is prone to drought. Regionally, an upward trend in drought-affected areas has been detected in three regions (Inner Mongolia, Northeast and North) from 1951-2009. However, the decadal variability of droughts has been weak in the rest of the five regions (South, Southwest, East, Northwest, and Tibet). Xinjiang has even been showing steadily wetter since the 1950s. Two regional dry centres are discovered in China as the result of a combined analysis on the occurrence of drought events from both grid points and drought study regions. The first centre is located in the area partially covered by the North and the Northwest, which extends to the southeastern portion of Inner Mongolia and the southwest part of Northeast. The second one is found on the central to southern portion of the South. Our study demonstrates the applicability and the value of using modeled soil moisture for reconstructing drought histories, and the SMAPI is useful for analyzing drought at different spatial and temporal scales. [ABSTRACT FROM AUTHOR]

In order to investigate the operation performance of ground-coupled heat-pump (GCHP) system, an analytical simulation model of GCHP system on short time-step basis and a computer program based on this model to predict system operating parameters are developed in this study. Besides, detailed on-site experiments on GCHP test rig installed in a temperate region of China are carried out. The temperature distributions of borehole as well as ground around borehole at different depths are evaluated. Operation parameters of GCHP system such as circulating water temperature, heat rejection into ground and system power consumption when the system operated in intermittent and continuous modes are investigated. The accuracy of proposed simulation model is validated by experimental data. The advantage of GCHP technology in energy efficiency over other conventional air-conditioning systems is proved to be obvious and the performance of GCHP system is found to be affected by its operation modes. [ABSTRACT FROM AUTHOR]

If prediction of a debris landslide is to be completed, the first problem is how to determine and correlate the dynamic factors. The special composition and complicated geological conditions of debris landslides have many dynamic factors influencing displacement and stability. Correlations are generally very complicated. The relationship and sequence of factors is too complex to be completed by traditional mathematical model. In order to solve the problem above, a systematical study of the quantitative and qualitative dynamic factors using a model of the quantitative theory was performed based on the displacements of Xintan landslide, China. Rainfall was found to be the most important dynamic factor among the six factors controlling displacements. Relative importance sequence and correlation was also established. All prediction results agree with the mechanism and displacement pattern of the Xintan landslide. Optimized measures of prevention and control for debris landslides can be completed with correlation of the dynamic factors by means of the quantitative theory model. [ABSTRACT FROM AUTHOR]