In this paper, a new predictive model, adapted to QTM (Quaternary Triangular Mesh) pixel compression, is introduced. Our approach starts with the principles of proposed predictive models based on available QTM neighbo...In this paper, a new predictive model, adapted to QTM (Quaternary Triangular Mesh) pixel compression, is introduced. Our approach starts with the principles of proposed predictive models based on available QTM neighbor pixels. An algorithm of ascertaining available QTM neighbors is also proposed. Then, the method for reducing space complexities in the procedure of predicting QTM pixel values is presented. Next, the structure for storing compressed QTM pixel is proposed. In the end, the experiment on comparing compression ratio of this method with other methods is carried out by using three wave bands data of 1 km resolution of NOAA images in China. The results indicate that: 1) the compression method performs better than any other, such as Run Length Coding, Arithmetic Coding, Huffman Cod- ing, etc; 2) the average size of compressed three wave band data based on the neighbor QTM pixel predictive model is 31.58% of the origin space requirements and 67.5% of Arithmetic Coding without predictive model.展开更多
Poor countries are prone to climate change effects due to lack of mechanisms to mitigation. As such, they are most vulnerable to effects of climate changes which are floods, drought, deforestation, environmental degra...Poor countries are prone to climate change effects due to lack of mechanisms to mitigation. As such, they are most vulnerable to effects of climate changes which are floods, drought, deforestation, environmental degradation and so on. Many of affected communities particularly in rural areas and urban poor have resorted to migration to viable agricultural lands and urban areas increasing pressure on available social services. This situation has led to depletion of natural resources in the fringes of the cities in search for shelter, food, water, energy etc.. Dares Salaam city is highly prone to environmental degradation by being highly populated and closer to the Kazimzumbwi Forest National Reserve, which has been a resource of logging at the guise of sustainable livelihood of Dares Salaam city residents. This paper is reporting on a study undertaken in ENVI ＆ ARCGIS software environment to evaluate the extent of environmental degradation in the forest reserve for the period of 16 years i.e. 1995-201 l, firstly, for purpose of informing policy makers and administrators to determine the extent of the problem and secondly to provide evidence for development of effective mitigation measures. Results revealed a considerable environmental degradation within the forest reserve over the study period. This was attested by a decrease of forests by 42%, grass land, as well as increase of bare land and grass land by 26% and 42% respectively. This is a testimony that there was a significant environmental degradation and loss of natural resources during the study period which should be addressed by relevant authorities.展开更多
Sustainable development indicators, aim to measure sustainable development over longer periods of time. The sustainable development indicators are grouped into 10 subject categories： socioeconomic development, sustai...Sustainable development indicators, aim to measure sustainable development over longer periods of time. The sustainable development indicators are grouped into 10 subject categories： socioeconomic development, sustainable consumption and production, social inclusion, demographic changes, public health, climate change and energy, sustainable transport, natural resources, global partnership and finally good governance. In this paper, the authors examined a number of researches and compared the methods they used in order to determine the advantages and disadvantages of each method. The methods used a large number of different indicators. The comparison of the indicators could be made through mathematical models and also through theoretical approach.展开更多
基金Project 40471108 supported by the National Natural Science Foundation of China
文摘In this paper, a new predictive model, adapted to QTM (Quaternary Triangular Mesh) pixel compression, is introduced. Our approach starts with the principles of proposed predictive models based on available QTM neighbor pixels. An algorithm of ascertaining available QTM neighbors is also proposed. Then, the method for reducing space complexities in the procedure of predicting QTM pixel values is presented. Next, the structure for storing compressed QTM pixel is proposed. In the end, the experiment on comparing compression ratio of this method with other methods is carried out by using three wave bands data of 1 km resolution of NOAA images in China. The results indicate that: 1) the compression method performs better than any other, such as Run Length Coding, Arithmetic Coding, Huffman Cod- ing, etc; 2) the average size of compressed three wave band data based on the neighbor QTM pixel predictive model is 31.58% of the origin space requirements and 67.5% of Arithmetic Coding without predictive model.
文摘Poor countries are prone to climate change effects due to lack of mechanisms to mitigation. As such, they are most vulnerable to effects of climate changes which are floods, drought, deforestation, environmental degradation and so on. Many of affected communities particularly in rural areas and urban poor have resorted to migration to viable agricultural lands and urban areas increasing pressure on available social services. This situation has led to depletion of natural resources in the fringes of the cities in search for shelter, food, water, energy etc.. Dares Salaam city is highly prone to environmental degradation by being highly populated and closer to the Kazimzumbwi Forest National Reserve, which has been a resource of logging at the guise of sustainable livelihood of Dares Salaam city residents. This paper is reporting on a study undertaken in ENVI ＆ ARCGIS software environment to evaluate the extent of environmental degradation in the forest reserve for the period of 16 years i.e. 1995-201 l, firstly, for purpose of informing policy makers and administrators to determine the extent of the problem and secondly to provide evidence for development of effective mitigation measures. Results revealed a considerable environmental degradation within the forest reserve over the study period. This was attested by a decrease of forests by 42%, grass land, as well as increase of bare land and grass land by 26% and 42% respectively. This is a testimony that there was a significant environmental degradation and loss of natural resources during the study period which should be addressed by relevant authorities.
文摘Sustainable development indicators, aim to measure sustainable development over longer periods of time. The sustainable development indicators are grouped into 10 subject categories： socioeconomic development, sustainable consumption and production, social inclusion, demographic changes, public health, climate change and energy, sustainable transport, natural resources, global partnership and finally good governance. In this paper, the authors examined a number of researches and compared the methods they used in order to determine the advantages and disadvantages of each method. The methods used a large number of different indicators. The comparison of the indicators could be made through mathematical models and also through theoretical approach.
