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Land-use change simulation for large-scale regions (i.e. provincial regions or countries) is very useful for many global studies. Such simulation, however, is affected by computational capability of general computers. This paper proposes a method to implement cellular automata (CA) for land use change simulation based on graphics processing units (GPUs). This method can be applied to large-scale land-use change simulations by combining the latest GPU high-performance computing technology and CA. We carried out the experiments by simulating land-use change processes at a provincial scale. This involves a lot of sophisticated techniques, such as model mapping, and computational procedure of GPU-CA model. This proposed model has been validated by land-use change simulation in Guangdong Province, China. The comparison indicates that the GPU-CA model is faster than traditional CA by 30 times. Such improvement is crucial for land-use change simulations in provincial regions and countries. The outputs of the simulation can be further used to provide information to other global change models. [ABSTRACT FROM AUTHOR]

Abstract: To find the key impact factors of CO2 emissions to realize the carbon intensity target, this paper examined the impact factors of population, economic level, technology level, urbanization level, industrialization level, service level, energy consumption structure and foreign trade degree on the energy-related CO2 emissions in Guangdong Province, China from 1980 to 2010 using an extended STIRPAT model. We employed ridge regression to fit the extended STIRPAT model. Empirical results indicate that factors such as population, urbanization level, GDP per capita, industrialization level and service level, can cause an increase in CO2 emissions. However, technology level, energy consumption structure and foreign trade degree can lead to a decrease in CO2 emissions. The estimated elastic coefficients suggest that population is the most important impact factor of CO2 emissions. Industrialization level, urbanization level, energy consumption structure, service level and GDP per capita are also significant impact factors, but the other factors such as technology level and foreign trade degree are less important impact factors. Some policy recommendations are also given on how to mitigate the growth of CO2 emissions. [Copyright &y& Elsevier]

Abstract: The exploitative intensity evaluation of bays is meaningful for the ecological conservation, future utilization and integrated management of bays in China; especially for the regions where the economic development is depending on the coastal exploitation. Nevertheless, the complexity of morphology and structure of bays make the study a little bit difficult. A physical impulse-based approach to evaluate the exploitative intensity of bay was put forward in this paper. First of all, the differentiation in morphological, spatial location and structure of bays were analyzed, and the bay was separated into geographical elements of axes and areas accordingly; secondly, the exploitation and utilization process was abstracted and assumed using physical principles; Thirdly, physical Impulse-based Model of exploitative intensity evaluation was build according to the Law of Momentum which can convert the process variable to state variable. Daya Bay of Guangdong province in China was taken as a case study, four key time indicating the construction of large coastal engineering near Daya Bay coast were selected, namely year 1986, 1991, 2001 and 2004. The exploitative intensities of each spatial element of Daya Bay during 1986–1991, 1991–2001, and 2001–2004 were calculated and analyzed. The results show that the exploitative intensity of intertidal flat in Daya Bay during the study time spans is highest. The potential applications, current limitations, and future challenges of the approach were discussed. [Copyright &y& Elsevier]

Abstract: Flood disasters are one of the most common and destructive natural hazards all over the world. In this paper, improved interior-outer-set model (IIOSM) based on information diffusion theory is introduced in detail to assess flood risk in an effort to obtain accurate analytical results that represent the actual situation. Then fuzzy α-cut technique is applied to calculate the fuzzy expected values under the possibility–probability distribution (PPD) calculated by IIOSM. Taking the value of α throughout the interval (0,1], we correspondingly get access to the conservative risk value (R C ) and venture risk value (R V ). Selection of α, R C and R V is dependent on present technical conditions and risk preference of different people. To illustrate the procedure of IIOSM and fuzzy α-cut technique, we employ them respectively to analyze the flood risk in Sanshui District, located in the center of Guangdong province in China. The results, such as risk value estimations, as well as fuzzy expected values, i.e. R C and R V under the given α-cut level, can reflect the flood risk quite accurately. The outcomes of this research based on IIOSM and fuzzy α-cut technique offer new insights to carry out an efficient way for various flood protection strategies. [Copyright &y& Elsevier]

Abstract: Rabies is a major public health problem in some developing countries including China. One of the reasons is that there is a very large number of dogs, both domestic and stray, especially in Guangdong Province which has the third most rabies cases (after Guangxi and Hunan) among the 31 provinces, autonomous regions and municipalities in Mainland China, and at least 18.2% of the human rabies cases are caused by stray dogs. In this paper, based on the reported data and characteristics of the rabies infection in Guangdong Province, we propose a mathematical model for the dog–human transmission of rabies. We first determine the basic reproduction number R 0 and discuss the stability of the disease-free equilibrium and persistence of the disease. By carrying out sensitivity analysis of the basic reproduction number in terms of some parameters, we find that the domestic dog vaccination rate, the recruitment rate of domestic dogs, and the quantity of stray dogs play important roles in the transmission of rabies. This study suggests that rabies control and prevention strategies should include public education and awareness about rabies, increase of the domestic dog vaccination rate and reduction of the stray dog population. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a set of numerical models focussing on structural controls on hydrothermal mineralization. We first give an overview of natural phenomena of structurally-controlled ore formation and the background theory and mechanisms for such controls. We then provide the results of a group of simple 2D numerical models validated through comparison with Cu-vein structure observed near the Shilu Copper deposit (Yangchun, Guangdong Province, China) and finally a case study of 3D numerical modelling applied to the Hodgkinson Province in North Queensland (Australia). Two modelling approaches, discrete deformation modelling and continuum coupled deformation and fluid flow modelling, are involved. The 2D model-derived patterns are remarkably consistent with the Cu-vein structure from the Shilu Copper deposit, and show that both modelling approaches can realistically simulate the mechanical behaviours of shear and dilatant fractures. The continuum coupled deformation and fluid flow model indicates that pattern of the Cu-veins near the Shilu deposit is the result of shear strain localization, development of dilation and fluid focussing into the dilatant fracture segments. The 3D case-study models (with deformation and fluid flow coupling) on the Hodgkinson Province generated a number of potential gold mineralization targets. [Copyright &y& Elsevier]

This paper presents a novel mathematical model with multidrug-resistant (MDR) and undetected TB cases. The theoretical analysis indicates that the disease-free equilibrium is globally asymptotically stable if R0 < 1; otherwise, the system may exist a locally asymptotically stable endemic equilibrium. The model is also used to simulate and predict TB epidemic in Guangdong. The results imply that our model is in agreement with actual data and the undetected rate plays vital role in the TB trend. Our model also implies that TB cannot be eradicated from population if it continues to implement current TB control strategies. [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]