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Based on multi-temporal remote sensing images, the building land index (BAI) of Yuxi City in 1995, 2005 and 2015 was extracted. The spatial and temporal characteristics of urban expansion in Yuxi City in recent 20 years were studied by selecting the expansion rate, expansion intensity, dynamic attitude, expansion degree, compactness and fractal dimension.The results showed that :(1) From 1995 to 2015, the building land in Yuxi City has been in a state of rapid expansion, the area of building land increased from 131.21km2 to 416.66km2, expanding by 284.45km2.(2)The compactness of urban shape has been increasing from 0.033 to 0.058, an increase of 0.025. The overall spatial pattern was becoming more and more compact, and the fractal dimension and stability was constantly declining.The urban form was complex and in an unstable state. In the future, reasonable policies should be formulated to adjust the spatial distribution and expansion mode of building land to achieve sustainable development.

How to quantitatively measure and identify the characteristics of urban landscape expansion is an important scientific problem facing rapid urbanization. The Multi-order Adjacency Index (MAI) can be used to measure the degree of urban expansion at multiple consecutive points in time, and has significant advantages in characterizing urban landscape expansion. This paper takes Chenggong District of Kunming City as the research area, selects 6 remote sensing images (2005, 2010, 2013, 2015, 2017 and 2018) to divide 5 time periods, and uses MAI to analyze the change process of urban landscape pattern in Chenggong District of Kunming City. The experimental results show that: (1) Relying on the expansion of the original construction land is the main mode of urban expansion in Chenggong District; (2) The degree of urban expansion in Chenggong District decreases with the attenuation of the spatial distance between new and old patches; (3) Generally speaking , The urban expansion rate of Chenggong District has gradually slowed down, and the urban expansion pattern has become more compact.

This article uses 20 years of remote sensing image maps of Kunming City as the basis, and calculates the city’s impervious surface change, expansion intensity index, compactness change index and other indicators to analyze the dynamic changes of Kunming’s urban land in terms of time series and spatial form Perform monitoring and analysis. It also discusses the driving factors of urban land expansion in combination with the socio-economic development of the study area and the natural geographic environment. Research shows that: (1) From 2000 to 2020, the area of urban construction land in the cities under the jurisdiction of Kunming continues to increase, and the overall trend is steady. (2) The urban land expansion intensity of the built-up area of Kunming City showed an overall trend of increasing first and then decreasing, showing phased characteristics; (3) According to the calculation of the Richardson compactness index, it is known that from 2000 to 2020, Kunming City The intensity of urban land expansion and compactness is generally on the rise year by year.

Based on multi-temporal remote sensing images, the vegetation information of Yuxi City in 1995, 2005 and 2015 was extracted by using the normalized difference vegetation index ( NDVI ), and the pixel dichotomy model was used to calculate the vegetation coverage ( FVC ). The spatial and temporal characteristics of vegetation coverage area distribution in Yuxi City in recent 20 years were discussed by selecting the mean value of vegetation coverage and the transfer matrix of vegetation coverage grade area. The results showed that the area of middle and high vegetation coverage in Yuxi was more than 50 %, and the overall vegetation coverage was improved in from 1995 to 2015. In terms of spatial distribution, the overall vegetation coverage shows that the vegetation coverage in the northeast urban agglomeration area and both sides of the western valley is low, while the vegetation coverage in the southwest mountainous area is large. In the future, reasonable policies should be formulated to rationally use natural resources to enhance urban vegetation coverage, optimize land use structure, and realize the healthy and sustainable development of Yuxi City.

Considering the complex natural and human environmental factors in Yunnan Province, based on the meteorological, land use, DEM and MOD13A3 vegetation datas of four different years in 2005, 2010, 2015 and 2019 in Yunnan Province, 15 evaluation indexes including soil erosion intensity, landscape diversity index, net primary productivity of vegetation, annual temperature, annual precipitation and biological abundance were selected by using GIS and remote sensing technology combined with SRP model. The principal component analysis method was used to comprehensively and quantitatively study the spatial and temporal distribution characteristics of ecological vulnerability in Yunnan Province from 2005 to 2019. The results showed that: (1) From 2005 to 2019, the overall ecological vulnerability of Yunnan Province showed a trend of continuous improvement. The area of severely and extremely vulnerable areas decreased by 2833.09 km2 compared with 2005, and the improvement trend in 2015-2019 was the most obvious. The area of moderately, severely and extremely vulnerable areas decreased from 27015.66 in 2015 to 1325.68 km2 in 2019, and the proportion of slightly vulnerable areas increased from 88.3% in 2015 to 99.6%. (2) The severely and extremely vulnerable areas in Yunnan Province are mainly distributed in the central, northwest and northeast of Yunnan Province. The highest degree of ecological vulnerability is in the central Yunnan Province, and the extremely vulnerable area is about 443.8 km2. (3) Moderately vulnerable areas in Yunnan Province are mainly concentrated in southeast Yunnan; (4)The slightly vulnerable areas in Yunnan Province are mainly distributed in southwest Yunnan, accounting for 22.6% of the whole province.

With the development of economy, growth of population and urbanization, urban land is increasing and the speed of urban expansion is speeding up. Mastering the spatial-temporal process of urban expansion is of great significance for natural environment and human development. In this paper, taking the Dianchi Lake Basin as an example, based on the TM and OLI image data from 1990 to 2015, every five years as a time node, the decision tree classification method is used to extract and analyze the urban land for each period of image data. The results showed that the area of urban land in Dianchi Lake Basin increased from 1990 to 2015 with 462km2, with an average annual growth rate of 5.9%, of which the fastest expansion rate has occurred from 2010 to 2015. The impervious surface expansion is radiation-like growth centered around the urban area of Kunming, mainly in the eastern and northern parts of Dianchi.

Land Use and Land Cover Change (LUCC) is the essential content of the study of the current global environmental change and sustainable development, and has a profound influence on regional water cycle, atmospheric circulation, environmental quality, climate change, and terrestrial ecosystem productivity. It is also the most important reason causing biodiversity attenuation. The MAS/LUCC model of this paper is designed to explore the mechanism of the spatial and temporal evolution of the land use change, which results from the interaction among government, residents, farmers, and other agents, the interaction between multi-agent and the environment where the agents live. The model also introduces the ant colony optimization to improve the simulation accuracy. Taking Erhai Lake Basin as a case, MAS/LUCC used the watershed land use classification map in 2000 as the initial data, predicted and simulated the land use types and structure of the watershed in 2010, using the land use classification map of 2010 as validation data. The accuracy of the model is 79.71% or so by the point-to-point verification method, and the ant colony optimization improves the precision of 8.94% compared with the model without it. Thus, it can be able to provide auxiliary decision support for the government and land-use planners to develop a land policy.

This paper combines geographic information technology and casualties assessment model, research on how quickly to get the results of casualties assessment calculation. In this paper, we introduced GIS-based seismic casualties assessment system's principle and design, Five-story structure based system architecture, functional realize and other content. Use the 6.4 earthquake occurred in Ning'er County, Pu'er City, Yunnan Province as an example to make once casualties assessment, and made a brief analysis of the results.

In order to guide the city's waterlogging control, it's very necessary to research the urban waterlogging occurrence rules and how urbanization affects the urban waterlogging. In this paper, we select the catchment area located in Kunming Dongfeng East Road as study area to construct the urban waterlogging simulation model based on GIS and SWMM model. The procedure of model building contains sub-basin division, drainage system generalization, and parameter settings. Then different urbanization degrees and different rainfall return period settings will be tested on the constructed model. The results show that the model can be used for dynamically simulating urban waterlogging. Both runoff volume and peak flow increased significantly with increasing return period. In addition, with the development of urbanization, urban impervious area increased rapidly, but decreased in rainfall infiltration, while the risk of floods increased. This impact was more obvious in the short return period rainfall conditions.

This paper discusses how to use the ArcEngine components and Orcale database to quickly draw the Yunnan Province digital isoseisms. Besides the current general ellipse model, the paper was the first time to complete the line source model of isoseisms drawing. At the same time, it improved the Binary search algorithm in order to quickly find closest active fault. Then the existing isoseisms file provided three correction methods: parameter correction, aftershocks correction and manual correction, which were respectively applied for the different data and purpose of the correction. Finally, taking an example of the simulation for Ning'er 6.4 and Lijiang 7.0 earthquake to demonstrate the method of fast drawing Yunnan digital isoseisms, and the method turned out to be feasible and practicable.

This paper discusses the issues about the cyanobacteria bloom identification and monitoring methods based on MODIS satellite images of Dianchi Lake. Through a comparative analysis of the spectral characteristics on typical surface features (clean water, muddy water, vegetation and cyanobacteria) and different concentration of cyanobacteria bloom covering over the water surface of Dianchi Lake, we can get the response sensitive bands information of cyanobacteria bloom. We can also extract the spatial distribution and divide the concentration classification threshold of cyanobacteria bloom in Dianchi Lake by using false color synthesis (MODIS:6-2-1) method, single-band method, ratio vegetation index (RVI) method, normalized difference vegetation index (NDVI) method, enhanced vegetation index (EVI) method. At the same time, we can analyse the dynamic process about cyanobacteria bloom through multitemporal remote sensing images and difference operation.

Since AIDS was first discovered, mathematical models of the transmission dynamics of this disease have been developed to determine the drivers of the epidemic. It has become apparent that the most important factor in the propagation of the disease is the aggregate effects of individual behavior and perception of risk in a geographic environment. Agent-based models (ABM) allow one to simulate the social and sexual interactions which may describe the societal context in which HIV may spread easily. Using this framework, we develop an agent-based modeling approach to simulate sexual transmission of HIV/AIDS in an urban environment, as a result of individuals' interactions in a grid context. Individuals in a closed population are explicitly represented by agents associated to places where they interact with other agents. They are endowed with mobility, allowing them to move between places within the urban environment for representing the spatial heterogeneity and the complexity involved in HIV diffusion. In order to better describe agent's conduct, each agent has its only gender, age, sex partner, life expectancy, condom use and other attributes. In each time step, every agent may move, find sex partner, separate from his sex partner or die. The model is implemented on the Repast Simphony 1.2. The simulation results show the factors such as density of population, condom use and vision of people play significant roles in the spread of HIV/AIDS. So related departments should vigorously promote the use of condoms, pay more attention to key areas and strengthen moral education to slow down the speed of sexual transmission of HIV/AIDS when establishing measures in prevention and control the spreading of AIDS.

Evacuation simulation can greatly ease the cost of money and material in fire case by using computer. Integrating ABM and GIS technology can not only recurrent the evacuation process, but also analyse optimal evacuation route, optimize the supermarket layout by GIS spatial analysis functions. A model is used to determine the action rules of evacuation staff, simulate the evacuation process on Agent Analysis platform and get the change trend of people quantity over time.

BACKGROUD: Since Mexico reported the first case of Influenza A H1N1 influenza patients in March 2009, Influenza A H1N1 flu spreads rapidly around the world and threats seriously to human health. OBJECTVIES: (1) Establishing an Agent-based Model (ABM) of H1N1 transmission, simulating and predicting the distribution of location, extent and development of the law of H1N1 to explore the space-time propagation of H1N1. (2) Simulating how many people will be infected under different disease control strategies. (3) Helping decision-makers decide on the best strategy to mitigate the spread of infection. METHODS, Simulation core is built H1N1 propagation model base on ABM. This model consists of Agent, the environment and rules of three parts. H1N1 influenza has contagious, the short incubation period and the spread of strong characteristics. The paper is divided into five types of Agent according to these characteristics. The first is the health of Agent; The second is high-risk Agent; The third Agent is that H1N1 influenza virus has been transmitted but not yet diagnosed; The fourth Agent is that influenza A H1N1 influenza have been confirmed infected; The fifth is death Agent. Environment is the space in which Agent. It can be a two-dimensional grid, can be a network, can also be expressed by the vector or raster spatial data. In this paper we use the vector data. Rules are a source of Agent intelligence, Agent for all acts must follow the rules. H1N1 model includes acting rules, the state transformation rules and interact rules between Agents an environment. The acting rule is random movement rules in this article. Assuming a distance as the critical distance transmission of H1N1, more than this distance will not be infected with H1N1, but the closer the distance the higher rate of infection. The state transformation rule is SEIDR model. The interact rules between Agents an environment is the Agent and GIS integration. The paper makes Agent Analyst as the integration platform. The three rules in the whole simulation process is a whole and synchronous parallel occurrence. We can evaluate the results of different control measures by adjusting the rules' parameters during the simulation. Finally, we conducted an empirical study of Kunming as an example. RESULTS Different intensity of preventive measures to control the epidemic H1N1 plays a decisive role.

In 1989, HIV was detected amongst injecting drug users (IDUs) in Yunnan province. Needle sharing drove the epidemic and HIV spread rapidly to IDUs in neighboring cities and along drug trafficking routes. By 2002, HIV was present amongst IDUs in all mainland Chinese provinces. It is believed that IDUs may have been the core source for all later sub-epidemics in China. Agent-based modeling (ABM) is the dominant paradigm in social complex network simulation which allows one to simulate the complex systems emerge from the bottom-up are composed of a multitude of heterogeneous objects called agents. This article puts forward an HIV/AIDS spatial and temporal transmission model of IDUs based on the multivalent system and geographic information systems (GIS) in an urban environment, and simulates the HIV/AIDS spatial and temporal transmission process among injection drug users during 10 years on the Repast Simphony1.2 platform. In the model, the crowd is classified into 5 types: healthy person, HIV person, AIDS person, IDU person and HIV-IDU person. Individuals represented by agents are associated to places where they interact with each other. The relationship among different agents is described with random social network. To better represent individuals in reality, each agent has its only sex, age, career, education, geographic location and other attributes. In each time step, the model defines these agents' specific behavioral rules. The model is implemented using the propagation of HIV/AIDS among injection drug users in Yunnan province southwest of China as a case study. The simulation results show that the number of initial HIV in injection drug users, the proportion of needle sharing and individual social impact have influence on the spread of HIV/AIDS in Kunming. The results also reveal the increasing HIV/AIDS transmission among injection drug users and interpret the necessity of carrying out solutions to contain the transmission of HIV/AIDS.

The propagation of influenza through a population is an inherent spatial-temporal process of great importance for modern society. So a spatial explicit epidemiologic model of flu is proposed for a greater understanding of the disease's spatial diffusion through a network of human contacts. The objective of this study is to develop an agent-based modeling (ABM) approach that integrates geographic information system (GIS) to simulate the spread of influenza in an urban environment, as a result of individuals' interactions in a geospatial context. The methodology for simulating spatiotemporal dynamics of influenza propagation is presented. Based on Repast Simphony platform, and applying Java and GIS tools, this paper designs and develops a prototype system to carry out agent-based simulation of influenza transmission and control in a geographic environment. The model is implemented using the H1N1 outbreak in Kunming, Yunnan province, southwest of china in 2009 as a case study. Individuals in a closed population are explicitly represented by agents associated to places where they interact with other agents. They are endowed with mobility, through a transportation network allowing them to move between places within the urban environment, in order to represent the spatial heterogeneity and the complexity involved in infectious diseases diffusion. In the model, influenza is described with the mathematic relation between transmission probability, the distance of two individuals, latent period, the time of infected to die, cure rate and other parameters. User can change the simulation results through adjusting the value of time to hospital and so on. The results show that the GIS-agent based model designed for this study can be easily customized to study the spread dynamics of any other influenza by simply adjusting the disease parameters. This type of simulations can help to improve comprehension of disease spread dynamics and to take better steps towards the prevention and control of an influenza outbreak.