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Abstract: The benefits of Integrated Water Resources Management (IWRM) are widely known but its recommendations remain thinly implemented. Designing wastewater treatment plants for reuse in irrigation is a particularly underutilized IWRM opportunity that could potentially increase agricultural yields, conserve surface water, offset chemical fertilizer demand, and reduce the costs of wastewater treatment by eliminating nutrient removal processes. This paper presents a novel planning model, consisting of a reuse-centric performance assessment and optimization model to help design wastewater treatment plants for reuse in agriculture. The performance assessment and optimization model are described, and their coupled application is demonstrated in the peri-urban district of Pixian, China. Based on the results of the performance assessment, two reuse scenarios are evaluated: wastewater to supplement business as usual (BAU) irrigation, and wastewater to replace BAU irrigation. The results indicate that wastewater supplementation could increase profits by $20 million (M) annually; alternatively, wastewater replacement could conserve 35Mm3 of water in local rivers each year. [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]

Abstract: Narrow bipolar events (NBEs) are a distinct class of intra-cloud lightning discharge. In this paper we present observations of 10 negative and 67 positive such events in East China. Positive NBEs occurred at 7–12km altitude above mean sea level (MSL) with a mean altitude of 9.5km, and negative NBEs occurred at 14–16km altitude. Electrical/channel characteristics of these events were derived from NBE pulse waveforms based on the transmission-line model. On average, the peak current moment and the charge moment change of a NBE event is 15kAkm, and 0.12Ckm, respectively. The mean time for the propagation of current front along the channel is 2.2μs. The upper limit on channel length for NBEs in this study is 510–1060m, the lower limit on discharge current amplitude is 12.5–43.2kA, and the minimum charge transfer is 0.1–0.3C. [Copyright &y& Elsevier]

Abstract: The downward solar or shortwave radiation (SWD) and atmospheric longwave radiation (LWD) play essential roles in controlling alpine environment and ecosystem. Meanwhile, utilization of solar energy has a growing demand by local residents, due to high energy cost in high altitude regions. However, it is always costly for acquiring the radiation data and there are few studies on the radiation modeling in these regions. This paper presented the major characteristics of SWD and LWD over the Tibetan Plateau (TP), which were measured at 11 stations built in the region. The results showed that LWD received by TP is much lower than that of its surrounding areas and their monthly-mean differences can be up to 100Wm−2. On the contrary, SWD over TP is significantly higher than that over its surrounding areas, due to low extinction rate of airmass, water vapor, and aerosol occurred in TP. The recorded maximum value (∼0.9) of daily-mean transmittances much exceeds the upper bound (∼0.75) implied in most of the Angström–Prescott models; therefore, these models may under-estimate SWD over TP. One set of surface data-based estimate by a non-Angström–Prescott model and two sets of satellite estimates were also evaluated against the measurements. It is found that the surface data-based estimate, though not calibrated locally, shows a good agreement with the measurements and has an advantage of producing less root-mean-square errors and higher correlation coefficients than the satellite estimates. Under this condition, it is suggested to combine both the surface data-based estimate together with the satellite estimates in order to improve the accuracy of the SWD and LWD data. [Copyright &y& Elsevier]

Abstract: A reliable supply of energy is essential to maintain and to improve human being''s living conditions. Compared to the conventional coal-fired approach, renewable energy (RE) helps to mitigate the impacts of greenhouse gas emissions to a large extent. As a newly developed sector with large resource potential and good commercial prospects, China''s wind power industry is exceeding expectations. By 2008, installed capacity of wind power in China totaled over 12GW, making China the fourth largest wind market in the world. However, China has to admit the gap with foreign leading countries, mainly in technical R&D for large-scale wind turbine generation units. This paper attempts to formulate an analytical model for studying and assessing factors that have significant impacts on the local industry. An improved dynamic Diamond Model is developed to help the international community to understand the status quo of the Chinese wind power industry. In order to build a stronger wind power industry, the elements identified in the model need to be strengthened. [Copyright &y& Elsevier]

Abstract: This paper introduced a stochastic programming model to address the air freight hub location and flight routes planning under seasonal demand variations. Most existing approaches to airline network design problems are restricted to a deterministic environment. However, the demand in the air freight market usually varies seasonally. The model is separated into two decision stages. The first stage, which is the decision not affected by randomness, determines the number and the location of hubs. The second stage, which is the decision affected by randomness, determines the flight routes to transport flows from origins to destinations based upon the hub location and realized uncertain scenario. Finally, the real data based on the air freight market in Taiwan and China is used to test the proposed model. [Copyright &y& Elsevier]

Abstract: Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel data. However, the conventional statistical methods used in land analysis have some limitations, especially in cases of limited observational data. In this paper, with the help of geographic information system (GIS) techniques, a partial least squares (PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of Beijing in China. From a preliminary analysis, four latent variables are selected: accessibility of the workplace center, livability, traffic, and environment facilities. The results show that the observation variables have a strong explanatory power for their corresponding latent variables, and the four latent variables have varying impacts on residential land prices. Of the latent variables, accessibility to the workplace center has the strongest impact on the residential land price. [Copyright &y& Elsevier]

Abstract: The paper develops a function of energy consumption, population growth, economic growth and urbanization process, and provides fresh empirical evidences for urbanization and energy consumption for China over the period 1978–2008 through the use of ARDL testing approach and factor decomposition model. The results of the bounds test show that there is a stable long run relationship amongst total energy consumption, population, GDP (Gross domestic product) and urbanization level when total energy consumption is the dependent variable in China. The results of the causality test with ECM (error correction model) specification, the short run and long run dynamics of the interested variables are tested, indicating that there exists only a unidirectional Granger causality running from urbanization to total energy consumption both in the long run and in the short run. At present, the contribution share which urbanization drags the energy consumption is smaller than that in the past, and the intensity holds a downward trend. Therefore, together with enhancing energy efficiency, accelerating the urbanization process that can cut reliance on resource and energy dependent industries is a fundamental strategy to solve the sustainable development dilemma between energy consumption and urbanization. [Copyright &y& Elsevier]

This paper presents a Modeling Approach to Resource economics decision-maKing in EcoaquaculTure (MARKET model). The MARKET model was developed as a scenario-testing tool to provide insights on the ecological and economic interactions, which is a critical issue for sustainable aquaculture management. As a case study, the model was applied to simulate shellfish production in an embayment located in the East China Sea. A set of scenarios was used to compare the model outputs with expected trends and to test its capability to simulate relevant management scenarios. The comparison of simulated scenarios indicates that the MARKET model outputs followed the expected trends regarding both standard economic theory for consumption and production, and ecological economic theory. In all the scenarios we tested the area available for aquaculture was found to impose a limitation on production before it became less profitable to expand production. As such, in this case study, the production in the long run does not meet increasing demand. Reduction of the maximum cultivation area was simulated in one of the scenarios as an example of a conservation measure. As expected there was a reduction of the net profit of the farmers compared with the standard simulation. On the other hand, this scenario combined with an increase in price growth rate simulates a compensatory measure that led to a net profit in the same range as observed in the standard simulation. Overall the MARKET model provides insights and raises questions useful for the implementation of an ecosystem approach to aquaculture. Further developments include the simulation of waste generated by cultivated species in order to better support sustainable management objectives. [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]

Abstract: Wind power in China registered a record level of expansion recently, and has doubled its total capacity every year since 2004. Many experts believe that China will be central to the future of the global wind energy market. Consequently, the growth pattern of wind power in China may be crucial to the further development of the global wind market. This paper firstly presented an overview of wind energy potential in China and reviewed the national wind power development course in detail. Based on the installed wind capacity in China over the past 18 years and the technical potential of wind energy resources, the growth pattern was modeled in this study for the purpose of prospect analysis, in order to obtain projections concerning the development potential. The future perspectives of wind energy development in China are predicted and analyzed. This study provides a comprehensive overview of the current status of wind power in China and some insights into the prospects of China''s wind power market, which is emerging as a new superpower in the global wind industry. [Copyright &y& Elsevier]

Abstract: This paper presents a model to quantify the impact of electric power outages on GDP by using Cobb–Douglas production function to develop an economic relationship between the reliability of the electric power supply system and the cost of electric energy unserved. Our findings show that average costs for providing a stable power supply are much lower than disruption costs, which is supported by recurring to the data available of Shanghai. Estimated by using Shanghai’s macroeconomic data of 1990–2006, this relationship indicates that the impact of electricity service disruption on Shanghai’s GDP is about 48.18×108 CNY in 2006, matching an alternative “back-of-envelope” estimate of 50.91×108 CNY. The estimated costs per kWh unserved are 1.81–10.26 CNY in 1990–2006, mirroring the increasing importance of electricity in the period’s economic development. These results demonstrate the usefulness of our approach for quantifying the reliability benefits of investments in electricity infrastructure. [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]

Abstract: The paper has been developed in the framework of a larger research program, in which the University of Rome “Tor Vergata” (Italy) and the Yangzhou University (China) are jointly involved to study and preserve historic towers. The research aims to evaluate the risk of collapse of the Huzhu Pagoda in Songjiang County, a leaning tower built in the XI century. Mechanical properties of the masonry material have been obtained by experimental tests on small specimen and the mechanical behaviour of the structure has been evaluated via numerical models. The static analysis of this ancient pagoda constitute a prerequisite base for the evaluation of its structural behavior leading to a suitable maintenance program. The architectural characteristics and damage conditions of the pagoda are key parameters in the preparation of a complex analytical model. The pagoda leans more than six and half degrees, and exhibits some bad structural conditions. Static analysis is carried out via finite-element method in order to establish a reliable numerical model and assess the static risk. [Copyright &y& Elsevier]

Abstract: In this paper, the time series method is used to analyze the effect of fire disasters and serious fires on monthly fire occurrence statistics in 10 cities from January 1997 to December 2001 in Jiangsu province. After removal of outliers in the irregular component of the original data series and seasonal adjustments, the intervention model is applied to quantify the effect of the fire disasters and serious fires on the total monthly fire statistics in the cities of Jiangsu province. The results show that the impact on monthly fires lasts for 3 months for eight cities and 2 months for two cities. Other phenomena are also detected in these 10 cities. Finally, some explanations for these phenomena are proposed. [Copyright &y& Elsevier]

Abstract: The identification of a deeply-buried petroleum-source rock, owing to the difficulty in sample collection, has become a difficult task for establishing its relationship with discovered petroleum pools and evaluating its exploration potential in a petroleum-bearing basin. This paper proposes an approach to trace a deeply-buried source rock. The essential points include: determination of the petroleum-charging time of a reservoir, reconstruction of the petroleum generation history of its possible source rocks, establishment of the spatial connection between the source rocks and the reservoir over its geological history, identification of its effective source rock and the petroleum system from source to trap, and evaluation of petroleum potential from the deeply-buried source rock. A case study of the W9-2 petroleum pool in the Wenchang A sag of the Pearl River Mouth Basin, South China Sea was conducted using this approach. The W9-2 reservoir produces condensate oil and gas, sourced from deeply-buried source rocks. The reservoir consists of a few sets of sandstone in the Zhuhai Formation, and the possible source rocks include an early Oligocene Enping Formation mudstone and a late Eocene Wenchang Formation mudstone, with a current burial depth from 5000 to 9000m. The fluid inclusion data from the reservoir rock indicate the oil and the gas charged the reservoir about 18–3.5Ma and after 4.5Ma, respectively. The kinetic modeling results show that the main stages of oil generation of the Wenchang mudstone and the Enping mudstone occurred during 28–20Ma and 20–12Ma, respectively, and that the δ13C1 value of the gas generated from the Enping mudstone has a better match with that of the reservoir gas than the gas from the Wenchang mudstone. Results from a 2D basin modeling further indicate that the petroleum from the Enping mudstone migrated upward along the well-developed syn-sedimentary faults in the central area of the sag into the reservoir, but that the petroleum from the Wenchang mudstone migrated laterally first toward the marginal faults of the sag and then migrated upward along the faults into shallow strata. The present results suggest that the trap structure in the central area of the sag is a favorable place for the accumulation of the Enping mudstone-derived petroleum, and that the Wenchang mudstone-derived petroleum would have a contribution to the structures along the deep faults as well as in the uplifted area around the sag. [Copyright &y& Elsevier]

This paper investigates the existence and direction of Granger causality between economic growth, energy consumption, and carbon emissions in China, applying a multivariate model of economic growth, energy use, carbon emissions, capital and urban population. Empirical results for China over the period 1960–2007 suggest a unidirectional Granger causality running from GDP to energy consumption, and a unidirectional Granger causality running from energy consumption to carbon emissions in the long run. Evidence shows that neither carbon emissions nor energy consumption leads economic growth. Therefore, the government of China can purse conservative energy policy and carbon emissions reduction policy in the long run without impeding economic growth. [Copyright &y& Elsevier]

Summary: In this paper, the Genetic Algorithms (GA) and Bayesian Model Averaging (BMA) were used to simultaneously conduct calibration and uncertainty analysis for the Soil and Water Assessment Tool (SWAT). In this combined method, several SWAT models with different structures are first selected; next GA is used to calibrate each model using observed streamflow data; finally, BMA is applied to combine the ensemble predictions and provide uncertainty interval estimation. This method was tested in two contrasting basins, the Little River Experimental Basin in Georgia, USA, and the Yellow River Headwater Basin in China. The results obtained in the two case studies show that this combined method can provide deterministic predictions better than or comparable to the best calibrated model using GA. The 66.7% and 90% uncertainty intervals estimated by this method were analyzed. The differences between the percentage of coverage of observations and the corresponding expected coverage percentage are within 10% for both calibration and validation periods in these two test basins. This combined methodology provides a practical and flexible tool to attain reliable deterministic simulation and uncertainty analysis of SWAT. [Copyright &y& Elsevier]

Abstract: This paper discusses migration styles and primary controls of petroleum migration pathways in heterogeneous carrier beds in the Damintun Depression, Bohai Bay Basin. There are two types of crude oils in the Damintun Depression: a high wax oil (wax hydrocarbon content between 8 and 60%) and a normal oil (wax hydrocarbon content lower than 8%). The high wax oil and normal oil are distinctly different both in biomarker compositions and in distribution patterns of carbon isotopic ratios for individual alkanes, and were confirmed to have been generated from different source rocks. Modeling of secondary migration pathways of both the high wax oil and the normal oil was conducted using a simple three-dimensional model, which assumes that the positions of petroleum migration pathways are controlled by the morphology of the sealing surfaces without taking into consideration the influence of permeability heterogeneity (the morphology-controlled migration model). The modeling results have reasonably well predicted the occurrences of both the high wax oil and the normal oil. All commercial petroleum accumulations are along the predicted preferential petroleum migration pathways (PPMP) formed by focusing of numerous “small petroleum streams” close to the kitchens. The focusing of oils originating from a large area of the generative kitchens is essential for the formation of large oilfields. The strong porosity and permeability heterogeneities of the carrier beds, and the relatively high prediction accuracy of the modeling, suggest that the preferential petroleum migration pathways, although influenced by permeability contrast at local scales, can be effectively predicted at a basin or depression scale under certain circumstances using a model that does not take into consideration the effect of heterogeneity. Most dry holes are not on the predicted petroleum migration pathways, suggesting that the three-dimensional migration pathway modeling may provide a useful tool to reduce exploration risk. [Copyright &y& Elsevier]

Abstract: During the 1990s, Chinese state-owned enterprises (SOEs) and collective enterprises continually decreased coverage of public health insurance to their employees. This paper investigates this changing pattern of health insurance coverage in China using panel data from the China Nutrition and Health Survey (1991–2000). It is the first attempt in this literature that tries to identify precisely the effects of specific policies and reforms on health insurance coverage in the transitional period of China. The fixed effects linear model clustering at the province level is used for estimation, and results are compared to alternative models, including pooled OLS, random effects GLS model and fixed effects logit model. Strong empirical evidence is found that unemployment as a side effect of the Open Door Policy, and the deregulation of SOE and collective enterprises were the main causes for the decreasing trend. For example, urban areas that were highly affected by the Open Door Policy were associated with 17 percentage points decrease in the insurance coverage. Moreover, I found evidence that the gaps between SOE and non-SOE employees, collective and non-collective employees, urban and rural employees have considerably decreased during the ten years. [Copyright &y& Elsevier]

Abstract: An ideal multi-objective financial decision support (MFDS) model for contractors should have ability of handling both the quantitative and qualitative inputs. This paper aims to develop a new MFDS model, which attempts to provide a more accurate way to support financial decision-makers in Chinese state-owned construction firms. Owing to the slow progress of passing the construction regulations, coupled with the inherited ownership problems in the Chinese booming construction industry, it is logical for Chinese project managers to make financial decisions with the consideration of the four objective functions (profit margin, risk factors, government relationship and market share), which are realistic representations of the present situation of Chinese construction industry. The proposed MFDS model is a practical method to support financial decision-making. For the model''s computational performance, Module 3 (stochastic universal sampling selection, adaptive crossover and adaptive mutation of Genetic Algorithm) is more superior. [Copyright &y& Elsevier]

Harmful algal blooms (HABs) have drawn great attention in coastal areas worldwide in the past decades because of their multiple effects on marine ecosystems as well as public health. This study utilized geographic information system (GIS) techniques to analyze the primary data on HABs, as well as shellfish toxins data, in the East China Sea from 2000 to 2006. The frequency of HABs was mapped by kernel density estimation, and the relative risk posed by HABs was assessed based on their physical–chemical characteristics. In addition, the spatial patterns and the trend of HAB events were examined by nearest neighbor analysis and time series analysis, respectively. The results revealed that HAB events not only had an increasing trend and significant seasonality, but also were clustered in space and time. HAB events displayed a higher frequency and a higher risk in Zhejiang coastal waters, particularly in the Zhoushan Archipelago, the largest marine fishery in China. Shellfish toxins were detected in areas with high HAB risk, but were not correlated with the risk. This paper provides a novel method to assess the relative risk caused by HABs and some useful information for HAB monitoring and management and aquaculture development. [Copyright &y& Elsevier]

Abstract: In addition to classical methods, namely kriging, Inverse Distance Weighting (IDW) and splines, which have been frequently used for interpolating the spatial patterns of soil properties, a relatively more accurate surface modelling technique is being developed in recent years, namely high accuracy surface modelling (HASM). It has been used in the numerical tests, DEM construction and the interpolation of climate and ecosystem changes. In this paper, HASM was applied to interpolate soil pH for assessing its feasibility of soil property interpolation in a red soil region of Jiangxi Province, China. Soil pH was measured on 150 samples of topsoil (0–20 cm) for the interpolation and comparing the performance of HASM, kriging, IDW and splines. The mean errors (MEs) of interpolations indicate little bias of interpolation for soil pH by the four techniques. HASM has less mean absolute error (MAE) and root mean square error (RMSE) than kriging, IDW and splines. HASM is still the most accurate one when we use the mean rank and the standard deviation of the ranks to avoid the outlier effects in assessing the prediction performance of the four methods. Therefore, HASM can be considered as an alternative and accurate method for interpolating soil properties. Further researches of HASM are needed to combine HASM with ancillary variables to improve the interpolation performance and develop a user-friendly algorithm that can be implemented in a GIS package. [Copyright &y& Elsevier]

Data envelopment analysis (DEA) requires input and output data to be precisely known. This is not always the case in real applications. This paper proposes two new fuzzy DEA models constructed from the perspective of fuzzy arithmetic to deal with fuzziness in input and output data in DEA. The new fuzzy DEA models are formulated as linear programming models and can be solved to determine fuzzy efficiencies of a group of decision-making units (DMUs). An analytical fuzzy ranking approach is developed to compare and rank the fuzzy efficiencies of the DMUs. The proposed fuzzy DEA models and ranking approach are applied to evaluate the performances of eight manufacturing enterprises in China. [Copyright &y& Elsevier]

Abstract: In this paper, a frozen soil parameterization scheme is developed based on the Common Land Model. We modify a frozen soil parameterization scheme using soil matric potential to define maximum liquid water content when soil temperature is below the freezing point; the simulation performance is validated using the data from Maqu station on the Tibetan Plateau from 2005 to 2006. The simulated results indicate that the modified frozen soil parameterization scheme allows the liquid water to exist when the soil temperature is below the freezing point, and the simulated soil liquid water content is significantly improved. The simulated soil temperature is also improved because of the successful simulation of the soil liquid water content. The distribution of energy from the modified model is closer to the observed data. Also, the simulated latent heat flux from the modified model increases and the simulated soil heat flux descends compared with the original model. [Copyright &y& Elsevier]

Nowadays, extensive research has been conducted to generate electricity from ocean waves, but there are not too many studies on the capture of wave energy in a specific ocean area. As the largest sea area in China's offshore waters, the South China Sea contains a large amount of wave energy and is regarded as a natural wave energy power plant. A comparative study was conducted to investigate the effects of wave energy converter (WEC) parameters on the long-term power capture performance of a bistable point absorber WEC installed in the South China Sea in this paper. Combined with the joint probability distribution of significant wave height H s and peak wave period T p in South China Sea, a mathematical model was developed for the evaluation of long-term power performance of WECs. The governing equations of the point absorber WEC were established using the hybrid frequency-time domain method. The dynamic response and captured power can be obtained after numerically solving the equations of motion with the 4th order Runge-Kutta Method. The results show that the bistable mechanism has great advantages in the long-term captured power of WEC. In general, a circular truncated cone-shaped buoy WEC with a larger buoy size and smaller nonlinear parameter tend to result in better long-term power capture performance. The insights given in this study provide a motivation and foundation for developing a complete set of performance optimization methods of point absorber WECs installed in South China Sea. • A mathematical model was developed for evaluation of long-term power performance of a point absorber WEC (PAWEC). • The long-term power performance of the WECs with and without bistable mechanism was numerically simulated. • The advantages of the bistable mechanism in the long-term captured power of WEC were confirmed. • The effects of WEC parameters on the long-term performance of the PAWEC were clarified. [ABSTRACT FROM AUTHOR]

Abstract: Soil nails have been widely used to stabilize slopes and earth retaining structures in many countries and regions, especially, in Hong Kong. The analysis of the interaction between a soil nail and the surrounding soil is of great interests to both design engineers and researchers. In this paper, authors present a simple mathematical model for the interaction analysis of a soil nail and the surrounding soil considering a few key factors which are soil dilation, bending of the soil nail, vertical pressure, and non-linear subgrade reaction stiffness. The lateral subgrade reaction between the soil and the soil nail is assumed to obey a hyperbolic relation. Reported test data in the literature are used to verify the present model. The contributions of the soil-nail bending on the pull-out resistance are evaluated in two case studies. [Copyright &y& Elsevier]

One primary action plan in the Healthy China 2030 initiative is to build innovativepatient referral models for health care reform in China. To ensure people have sufficient and equitable health care access when the patient referral policy is enforced, a systematic evaluation of its effects on the health care system is needed. In this paper, we focus on one health policy metric, the health care accessibility, by considering the patient transfer between different levels of health care facilities under the context that the need for specialized treatment cannot be fulfilled by a low-level facility. We then propose three conceptual patient referral models and a hierarchical two-step floating catchment area method to evaluate health care accessibility in different patient referral scenarios. A case study of hospitals in Beijing, China has been conducted to justify the proposed model, revealing the spatial inequality of health care accessibility. We find that while the patient referral can leverage health care resources to a certain extent, such effects are only prominent in areas with good coverage of health care facilities; and the efficiency of the health care system can be compromised in areas with limited health care provisioning. To this end, the study provides scientific evidence for the planning and reform of the health care policy in the Healthy China 2030 initiative. • H2SFCA model is proposed to model health care accessibility with patient referral. • Patient referral can leverage health care resources but compromise shortage areas. • The model provides decision support for health care planning of Healthy China 2030 [ABSTRACT FROM AUTHOR]

The waste-to-energy (WTE) project can handle the expanding volume of municipal solid waste (MSW) and promote the development of the circular economy, effectively. To achieve sustainable MSW management, it is pivotal to select a promising WTE incineration plant site. Thus, this paper aims to propose a novel methodology for selecting the optimal WTE incineration plant site. A sustainable evaluation index system is constructed from the environment, economy, society, risk, and energy aspects. Evaluation criteria are articulated by mathematical models and hesitant fuzzy linguistic term set, respectively. Given interactional relations among criteria and computation efficiency, HFL-BWM-ANP (hesitant fuzzy linguistic Best-Worst method-Analytic Network Process) is proposed to obtain criteria weights. The double parameters TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) approach is employed to rank alternative sites. The feasibility of the proposed methodology is illustrated by a numerical case. Triple sensitivity analysis and comparative analysis are performed to demonstrate the robustness, effectiveness, and superiority of the proposed methodology. Some managerial insights are provided from multiple dimensions for investors and the government to implement the WTE incineration plant project. Image 1 • Constructing a sustainable evaluation index system from multiple dimensions. • Articulating evaluation criteria by mathematical models and hesitant fuzzy linguistic term set, respectively. • Proposing a weighting model to improve efficiency and handle correlations among criteria. • Introducing the double parameters TOPSIS method to rank WTE incineration plant sites. • Providing managerial insights for investors and the government to manage WTE incineration plants. [ABSTRACT FROM AUTHOR]

• Free variables are selected based on mathematical model of hybrid cascaded MTDC. • System security operating range is analyzed to determine the free variables values. • An operation point calculation method for the hybrid cascaded MTDC is proposed. • The hybrid MTDC system operational dispatching and scheduling strategy is proposed. A hybrid cascaded Multi-terminal HVDC (MTDC) system involving both series and parallel-connected converters, which combines the advantages of line commutated converter based (LCC) and voltage source converter based (VSC) HVDC for ultra-high voltage, large-capacity and flexible power transmission, is proposed and is to be implemented in a real project in China. Due to complexity of operational control and difficulty of operational scheduling brought by the hybrid cascaded MTDC system and the lack of prior related research works, this paper establishes the mathematical model of the hybrid cascaded MTDC system and then proposes a system operational dispatching and scheduling strategy, which includes: 1) feasible coordinated operational control strategies investigation; 2) security operating range of the whole hybrid cascaded MTDC system analysis; 3) operating points of the hybrid cascaded MTDC system calculation. Simulations results based on PSCAD/EMTDC are used to validate the proposed system operational dispatching and scheduling strategy. [ABSTRACT FROM AUTHOR]

Urbanization results in a considerable economic disparity between urban and rural areas in developing countries, which has had a consequent significant impact on CO 2 emissions. To accommodate this directly, this paper presents a modified version of the Kaya Identity formula, U-Kaya, that includes a direct urbanization factor to determine the relationship between energy consumption intensity, population growth, urbanization rates, urban and rural GDP per capita and the volume of carbon emissions, for application in the dynamic forecasting of carbon emissions by Monte Carlo simulation. The method is demonstrated in forecasting China’s likely carbon emissions in 2020 by three different modes of urbanization policy: the government-dominant mode, market-dominant mode and a hybrid government market-dominant mode. The results indicate that a higher urbanization rate, energy carbon emission coefficient and energy intensity will lead to increased carbon emissions. Finally, three policy implications are identified, comprising the narrowing of the economic gap between urban and rural areas, adjustments to the energy structure and technical innovation, which will provide a valuable reference for developing countries in their efforts to reduce carbon emissions. [ABSTRACT FROM AUTHOR]

Abstract: The propulsion of the winter counter-wind current in the northern South China Sea (SCS) is investigated with a regional, three-dimensional, primitive equation model. This current is usually called the SCS Warm Current (SCSWC). Model results well reproduced the banded structure of the Guangdong coastal current, the SCSWC and the slope current from the coast to the slope in the northern SCS in the climatological data. The across-shelf flow is active in the shelf break area. Both onshore and offshore flows exist; the net across-shelf transport is shoreward throughout the year, and is larger in winter than in other seasons. The joint effect of baroclinicity and relief (JEBAR) is the dominant forcing of the across-shelf transport in the shelf break area. The major mass source of the SCSWC is the onshore-veered slope current. It is the JEBAR effect that supplies the necessary negative vorticity to maintain the slope current flowing across the isobaths and veering to the right hand to feed the SCSWC. Analyses of the momentum fields indicate that the onshore pressure gradient in the outer shelf balances the Coriolis force induced by the northeastward SCSWC in the frame of geostrophy. In winter, such an onshore pressure gradient is mainly provided by the strong density contrast between waters of the shelf and of the upper slope, which results from the Kuroshio intrusion via the Luzon Strait. The notable intrusion of the Kuroshio in winter is crucial for maintaining the density structure in the shelf break area and facilitates the set-up of the onshore pressure gradient over the outer shelf. [Copyright &y& Elsevier]

Abstract: This paper presents life-cycle-analysis (LCA) energy consumption (EC) and greenhouse gas (GHG) emissions of China’s current six biofuel pathways, which are: corn-derived ethanol (CE); cassava-derived ethanol (KE); sweet sorghum-derived ethanol (SE); soybean-derived bio-diesel (SB); jatropha fruit-derived bio-diesel (JB); and used cooking oil (UCO)-derived bio-diesel (UB). The tool utilized here is the WTW (Well-to-Wheels) module of Tsinghua-CA3EM model covering the entire lifecycle including: raw materials cultivation (or feedstock collection); fuel production; transportation and distribution; and application in automobile engines, compared with Conventional Petroleum-based gasoline and diesel Pathways (CPP). The results indicate: (1) the fossil energy inputs are about 1.0–1.5 times the energy contained in the fuel for the CE, SE and SB pathways, but 0.5–0.9 times for the KE, UB and JB pathways; (2) compared with CPP, the JB, KE and UB pathways can reduce both fossil fuel consumption and GHG emissions; the CE and SB pathways can only reduce fossil fuel consumption, but increase GHG emission; the SE pathway increases not only fossil fuel consumption but also GHG emission; and (3) the main factors inducing high EC and GHG emission levels include: high EC levels during the fuel production stage and high fertilizer application rates during the planting of raw feedstocks. Conclusions are that of the aforementioned biofuel pathways in China: (1) only the JB, KE and UB pathways have energy-saving merits as indicated by the LCA energy inputs and outputs; (2) compared with CPP, all but the SE pathway reduces fossil fuel consumption. However, the SB and CE pathway increase GHG emission; (3) all six displace petroleum by utilizing more coal; and (4) feedstock productivity levels must be increased, and there must be a reduction in fertilizer utilization and EC consumption during the cultivation and transportation stages in order to achieve the goals of energy balance and GHG emission reduction. [Copyright &y& Elsevier]