scholarly journals Modélisation de la survenue des vecteurs de la fièvre catarrhale ovine à l'aide des systèmes d'information géographiques et de la télédétection

2009 ◽  
Vol 62 (2-4) ◽  
pp. 154
Author(s):  
H. Martins ◽  
T. Nunes ◽  
Fernando Boinas
Keyword(s):  
Logistic Regression ◽  
Discriminant Analysis ◽  
Disease Transmission ◽  
Geographical Information Systems ◽  
Control Measures ◽  
Geographical Information ◽  
Analysis Model ◽  
Entomological Surveillance ◽  
Culicoides Imicola ◽  
Systèmes D’Information

Bluetongue (BT) is an infectious non-contagious disease which mainly affects domestic ruminants. It is caused by an arbovirus (BTV) from the family Reoviridae and its transmission is com­monly associated with an intermediate arthropod host from the genus Culicoides. Culicoides imicola is the main vector of BTV in the Mediterranean Basin. Entomological surveillance programmes make it possible to collect continuously data of vital importance for the spatial and temporal investigation of BT vector distribution. In May 2005, Portugal has implemented this programme, which is providing a considerable amount of data concerning the abundance, and spatial and temporal dis­tribution of several Culicoides species. Remote sensing is the process of acquiring data about a geographical object through several aircrafts or satellites built-in sensors and thus allowing the collection of useful information to characterize biophysical, climatic and environmental variables. Some of these variables influence survival, development and dispersion of BT vectors. The combination of satellite imagery and entomological surveil­lance data using geographical information systems (GIS) helps to develop models for the prediction of spatial occurrence of disease vectors. These models might be useful to identify risk areas for disease transmission and are therefore important for the development of targeted sanitary control measures. Two mathematical approaches were selected to model the spatial occurrence of Culicoides imicola, i.e. discriminant analysis and logistic regression. Climatic, remotely sensed and national entomological data were used to build both models. Statistical packages and GIS were then used to implement these models. The discriminant analysis model was less accurate, presenting a sensitivity of 76.6% and a specificity of 75.3%. The logistic regression model was more robust and presented 80.9% sensitiv­ity and 83.6% specificity. Descriptive spatial statistics were then calculated to characterize the landscape features associated with the presence/absence of BT vectors.

scholarly journals Evaluation du risque de la présence du vecteur de la fièvre catarrhale ovine basée sur des systèmes d'information géographiques et la modélisation statistique

2009 ◽  
Vol 62 (2-4) ◽  
pp. 177
Author(s):  
S. A. Pacheco ◽  
Y. M. Vaz ◽  
K. Fuchs
Keyword(s):  
Prevention And Control ◽  
Geographical Information Systems ◽  
Animal Health ◽  
Multiple Linear Regression Model ◽  
Geographical Information ◽  
Entomological Surveillance ◽  
Risk Maps ◽  
Systèmes D’Information ◽  
And Control ◽  
North Western

Bluetongue (BT) is among the World Animal Health Organization (OIE) listed diseases due to its potential for rapid spread and serious economic impact on livestock. Because of its epidemiology, in Europe, only Southern countries were affected by the disease in the past. However in the latter half of 2006, an unprecedented outbreak of bluetongue virus (BTV) serotype 8 occurred in North-Western European countries. To define potential regions that are at risk for BT epidemics it is essential to study vector distribution and abundance. This study focused on BT vector spread, mostly in Austria. The objective was to produce risk maps with the more likely areas for vector occurrence and thus to support BT prevention and control. The introductory review gives an overview of the epidemiology of the disease with a focus on the vectors, the recent outbreaks in North-Western Europe, and the importance of statistical model­ling and geographical information systems (GIS) in predicting, preventing and controlling BT.  The statistical analysis was mainly based on data from the Austrian entomological surveillance system, weather stations and topo­graphical information. A multiple linear regression model was fitted to the data to predict the occurrence of BTV vectors and subsequently to create risk maps for the whole country. Despite the fact that the limited nature of the data does not allow precise estimation, in general the models indicated that vectors occurred in preferential areas where they could be very abundant. A more detailed analysis should be carried out with a multidisciplinary team including epidemiologists, biologists, meteorologists, ento­mologists, and statisticians, so that the complexity of BT epide­miology may be better understood, and a more efficient process of prevention and control of the disease may be set up.

Transmission of SARS-CoV-2 in Different Districts of a County in Istanbul, March to September 2020

2021 ◽  
pp. 101053952110090
Author(s):  
Hüseyin Bilgin ◽  
Ahmet Topuzoğlu ◽  
Volkan Korten
Keyword(s):  
Public Transportation ◽  
Disease Transmission ◽  
Geographical Information Systems ◽  
Geographical Information ◽  
Chain Reaction ◽  
Heat Map ◽  
Large Populations ◽  
Polymerase Chain ◽  
Education Tool ◽  
Airborne Viruses

Epidemics caused by airborne viruses in cities with large populations create a big problem as in the current COVID-19 pandemic. Cramped lifestyle, busy workplaces, crowded public transportation, and higher household member counts are responsible for the transmission of the disease. In Turkey, Istanbul has taken the lead in the number of cases since the beginning of the epidemic. The excess population density is the major cause for disease transmission. It is essential to monitor the contaminated regions with geographical information systems on city maps. Outbreak maps visualize and help analyze the patterns of transmission and serve as a communication and education tool. A dynamic heat map video of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) polymerase chain reaction positive cases in a county of Istanbul was generated. The heat map visualizes how the epidemic spread to all the districts and the cumulative cases increased in one county of Istanbul with real attack rates.

scholarly journals A COMPARISON OF THE PREDICTIVE POWERS OF TENURE CHOICES BETWEEN PROPERTY OWNERSHIP AND RENTING

2019 ◽  
Vol 23 (2) ◽  
pp. 130-141 ◽  
Author(s):  
Chun-Chang Lee ◽  
Chih-Min Liang ◽  
Yang-Tung Liu
Keyword(s):  
Logistic Regression ◽  
Discriminant Analysis ◽  
Performance Prediction ◽  
Predictive Power ◽  
Cross Validation ◽  
Binary Logistic Regression ◽  
Analysis Model ◽  
Linear Modeling ◽  
Binary Logistic Regression Model ◽  
Hit Rate

This paper compares the predictive powers of hierarchical generalized linear modeling (HGLM), logistic regression, and discriminant analysis with regard to tenure choices between buying property and renting property by sampling the residents of the Greater Taipei area. The results imply that the hit rate and other indicators included in HGLM have better predictive power with regard to tenure choices than the binary logistic regression model and the discriminant analysis model. That is, using HGLM to process nested data can increase prediction accuracy regarding household tenure choices. Furthermore, cross-validation is performed to analyze hit rate stability. The hit rate sequencing from this cross-validation is found to be consistent with the HGLM results, implying that the comparison of the three models in terms of hit rate performance prediction in this study is stable and reliable.

scholarly journals Implementation of geographical information systems for the study of diseases caused by vector-borne arboviruses in Southeast Asia: A review based on the publication record

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Ajib Diptyanusa ◽  
Lutfan Lazuardi ◽  
Retnadi Heru Jatmiko
Keyword(s):  
Information Systems ◽  
Southeast Asia ◽  
Japanese Encephalitis ◽  
Disease Transmission ◽  
Geographical Information Systems ◽  
Temporal Dynamics ◽  
Geographical Information ◽  
Disease Manifestation ◽  
Research Activities ◽  
Vector Distribution

The spread of mosquito-borne diseases in Southeast Asia has dramatically increased in the latest decades. These infections include dengue, chikungunya and Japanese Encephalitis (JE), high-burden viruses sharing overlapping disease manifestation and vector distribution. The use of Geographical Information Systems (GIS) to monitor the dynamics of disease and vector distribution can assist in disease epidemic prediction and public health interventions, particularly in Southeast Asia where sustained high temperatures drive the epidemic spread of these mosquito-borne viruses. Due to lack of accurate data, the spatial and temporal dynamics of these mosquito-borne viral disease transmission countries are poorly understood, which has limited disease control effort. By following studies carried out on these three viruses across the region in a specific time period revealing general patterns of research activities and characteristics, this review finds the need to improve decision-support by disease mapping and management. The results presented, based on a publication search with respect to diseases due to arboviruses, specifically dengue, chikungunya and Japanese encephalitis, should improve opportunities for future studies on the implementation of GIS in the control of mosquito-borne viral diseases in Southeast Asia.

Visibility Analysis for Three-Dimension Urban Landscape

2012 ◽  
Vol 500 ◽  
pp. 458-464 ◽  
Author(s):  
Chang Lin Yin ◽  
Wen Qiang Xu ◽  
Qing Ming Zhan ◽  
Hong Hui Zhang
Keyword(s):  
Urban Space ◽  
Geographical Information Systems ◽  
Urban Landscape ◽  
Three Dimensional ◽  
Geographical Information ◽  
Three Dimension ◽  
Analysis Model ◽  
Visibility Analysis ◽  
Analysis Models ◽  
The Relationship

The visual sensation is an important factor in urban planning. A computer analysis technology based on the three-dimensional Geographical Information Systems (3DGIS) can be used to measure the visibility in urban space. The principle of sight calculations is introduced at first. The visibility analysis models about terrain and buildings are proposed. In terrain visibility analysis, a method based on projection and elevation interpolation is used to calculate the visibility of two points. And in building visibility analysis, another projection method is proposed to judge the relationship between the sight and building. Based on the visibility analysis of two points, an approximate visual field in a plane can be computed in a discrete way. The visibility analysis models are proved to be feasible. Further research that combines the visibility analysis model and the quantitative planning targets is suggested.

scholarly journals Evaluation of the impact of chemical control measures and entomological surveillance on Chagas' disease in the counties of Mambaí and Buritinópolis, Goiás State, Brazil

2001 ◽  
Vol 34 (6) ◽  
pp. 549-557 ◽  
Author(s):  
Antonio Carlos Silveira ◽  
Rosaura Peñaranda-Carrillo ◽  
Elias Seixas Lorosa ◽  
João Leite ◽  
Márcio Costa Vinhaes ◽  
...  
Keyword(s):  
Chagas Disease ◽  
Disease Transmission ◽  
Stomach Contents ◽  
Control Measures ◽  
Triatoma Infestans ◽  
Food Sources ◽  
Epidemiological Surveillance ◽  
Entomological Surveillance ◽  
Triatoma Sordida ◽  
The Impact

Epidemiological surveillance activities were implemented in 1980 in Mambaí and Buritinópolis counties, Goiás State. Twenty years later the authors evaluated the impact of these vector control measures on Chagas' disease transmission, based on entomological indicators. Entomological investigation was conducted using the man-hour technique and covering all domiciles. In order to study vector food sources the stomach contents of triatomines were analyzed using the modified precipitins technique. Triatomines were shown to be present in 48 (71.6%) of the 67 locations. Peridomiciliary infestation rates in Mambaí and Buritinópolis were 8.7% and 12.1%, respectively, while intradomiciliary rates were 0.7% and 1.2%. Triatoma sordida was the species identified in 97.3% of all captured specimens. It was also the only species found to be naturally infected with Trypanosoma cruzi. Birds were the most frequent food source (45%) for Triatoma sordida. The most significant result was the complete absence of Triatoma infestans in the two counties.

scholarly journals Dynamique spatio-temporelle de l’occupation du sol dans le Moungo, Région du Littoral, Cameroun : influence sur l’expansion des systèmes agroforestiers à base de bananiers

2020 ◽  
Vol 14 (2) ◽  
pp. 486-500
Author(s):  
Mélanie Rosine Tsewoue ◽  
Martin Tchamba ◽  
Marie Louise Avana ◽  
Armand Delanot Tanougong
Keyword(s):  
Land Use ◽  
Geographical Information Systems ◽  
Unsupervised Classification ◽  
Bare Soil ◽  
Agroforestry Systems ◽  
Geographical Information ◽  
Evolutionary Trend ◽  
Littoral Region ◽  
Open Forest ◽  
Systèmes D’Information

La présente étude vise à caractériser, sur 32 ans entre 1986 et 2018, les mutations spatio-temporelles qu’a connu la zone du Moungo dans la Région du Littoral au Cameroun en raison de l’expansion des plantations bananières et des diverses pressions dans l’utilisation des ressources. Les images satellitaires Landsat de 1986, 2001 et 2018 ont été exploitées à l’aide de la télédétection et des SIG. La classification non supervisée a permis d’obtenir huit classes d’occupation du sol (forêt dense, forêt claire, plantation et champs de cultures, sols nus, zone habitée, savane herbeuse et surface d’eau). La tendance évolutive des formations végétales est essentiellement régressive pour les forêts dense et claire avec une diminution de 336 924,51 ha à 272 887,04 ha entre 1986 et 2018, soit un taux de régression de 16,54% de la superficie totale. Par contre, elle est progressive pour les plantations/champs de cultures, savanes herbeuses, et zones habitées dont les superficies sont passées de 50 231,24 ha en 1986 à 111 325,41 ha en 2018 soit un taux de progression de 15,77%. Les facteurs de cette dégradation sont principalement d’ordres humains (agriculture, surpâturage et démographie galopante) et se traduit par la fragmentation des formations végétales naturelles au profit des surfaces cultivées et des zones d’habitations. Mots clés : Classes d’occupation du sol, facteurs de dégradation, Systèmes d’Information Géographique, Moungo-Cameroun. English Title: Spatio-temporal dynamic of land use change in the Moungo division, Littoral Region, Cameroon : influence on the expansion of banana-based agroforestry systems This study aims to characterize, over a 32-year period between 1986 and 2018, the spatial and temporal changes that occurs in the Moungo division located in the Littoral Region of Cameroon has undergone due to expansion bananas plantation and various pressures in the natural resources use. Landsat satellite images from 1986, 2001 and 2018 were exploited using remote sensing and GIS. The unsupervised classification yielded eight land use classes (dense forest, open forest, plantation and croplands, bare soil, inhabited area, herbaceous savannah and water plans). The evolutionary trend of vegetation formations is essentially regressive for dense and open forest with a decrease from 336 924.51 ha to 272 887.04 ha between 1986 and 2018, indicating a regression rate of 16.54% of the total area. On the other hand, it is progressive for plantations/croplands, herbaceous savannas, and inhabited areas, whose areas increased from 50 231.24 ha in 1986 to 111 325.41 ha in 2018, thus an increment rate of 15.77%. The degradation factors are mainly anthropogenic and include agriculture, overgrazing and increasing human population. As a result, the natural vegetation is being fragmented and transformed into cultivated areas and human inhabitations.Keywords : Land use classes, degradation factors, Geographical Information Systems, Moungo-Cameroon.

scholarly journals Hazard Assessments of Riverbank Flooding and Backward Flows in Dike-Through Drainage Ditches during Moderate Frequent Flooding Events in the Ningxia Reach of the Upper Yellow River (NRYR)

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1477
Author(s):  
Fuchang Tian ◽  
Bin Ma ◽  
Ximin Yuan ◽  
Xiujie Wang ◽  
Zhichun Yue
Keyword(s):  
Geographical Information Systems ◽  
Yellow River ◽  
Flood Hazard ◽  
Measurement Data ◽  
Control Measures ◽  
Geographical Information ◽  
Aerial Image ◽  
Drainage Ditches ◽  
Upper Yellow River ◽  
Flooding Events

In this study, the riverbank inundation caused by moderate frequent flooding events (with recurrence periods of less than 20 years), along with the increasingly serious hazards of backward flows in dike-through drainage ditches in the Ningxia Reach of the upper Yellow River (NRYR), were investigated. Then, a comprehensive method for hazard assessment of the floodplains and backward flows in the NRYR was proposed, which fully integrated geographical information systems (GISs), remote sensing (RS), and a digital elevation model (DEM), as well as river dynamics theory. This study first established a one-dimensional unsteady hydrodynamic model for the NRYR. The historical flood hydrology observation from 2012, along with the aerial image measurement data of the study area, were used to calibrate and verify the accuracy of the model. The hazards of riverbank inundation and damages to water affected engineering facilities, as well as the backward flows of dike-through drainage ditches caused by the moderate frequent flooding events, were comprehensively analyzed. Also, this study configured the hazard map and proposed revisions to the flood hazard ranking regime definitions, and discussed the impacts and prevention and control measures of moderate frequent flood damages. The proposed method could effectively meet the hazard analysis demands of the moderate frequent flooding events in the NRYR.

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