Predicting Joint Return Period Under Ocean Extremes Based on a Maximum Entropy Compound Distribution Model
Baiyu Chen,
Guilin Liu,
Liping Wang
Issue:
Volume 2, Issue 6, November 2017
Pages:
117-126
Received:
7 October 2017
Accepted:
8 November 2017
Published:
11 December 2017
DOI:
10.11648/j.ijees.20170206.11
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Abstract: In this paper, we proposed a novel 2-dimensional (2D) distribution model based on the maximum-entropy (ME) principle to predict the joint return period under ocean extremes. In detail, we first derive the joint probability distribution of the extreme wave heights and the extreme water-levels during a typhoon by using the maximum-entropy principle, and then we nest this distribution with the maximum-entropy distribution of discrete variables to form such a maximum-entropy 2-dimensional (ME 2D) compound distribution model. To evaluate the performance of our model, we conduct experiments to predict the N-year joint return-periods of the extreme wave heights and the extreme water levels in two areas of the East China Sea. According to the experimental results, our model performs better in predicting in the highly unpredictable joint probability of extreme wave heights and water levels in typhoon affected sea areas, compared with the widely-used Poisson-Mixed-Gumbel model in ocean engineering design. This ascribes to the fact that unlike other models whose corresponding parameters are arbitrarily assigned, our model utilizes both the new 2D distribution and the discrete distribution which are based on the ME principle.
Abstract: In this paper, we proposed a novel 2-dimensional (2D) distribution model based on the maximum-entropy (ME) principle to predict the joint return period under ocean extremes. In detail, we first derive the joint probability distribution of the extreme wave heights and the extreme water-levels during a typhoon by using the maximum-entropy principle, ...
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Assessment of Land Use/Cover Change and Urban Expansion Using Remote Sensing and GIS: A Case Study in Phuentsholing Municipality, Chukha, Bhutan
Chimi Chimi,
Jigme Tenzin,
Tshering Cheki
Issue:
Volume 2, Issue 6, November 2017
Pages:
127-135
Received:
19 October 2017
Accepted:
28 October 2017
Published:
11 December 2017
DOI:
10.11648/j.ijees.20170206.12
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Abstract: The rapid phase of urbanization and infrastructure development in Bhutan has been observed recently. This leads to causing of decrease in vegetation cover and growth in urban sprawl undergoing rapid land use/land cover change (LULC). This paper attempts to analyze the temporal and spatial patterns of LULC change and detects the urbanization processes of Phuentsholing city over a period of three decades (1996-2016) using multi temporal remotely sensed data. For this, the satellite images of Landsat 5, 7 and 8 were used to assess the changes of vegetation cover, built form and water bodies. This study has found that urban built area was increased from 6.7% in 1996 to 17% in 2016 and similarly vegetation cover was declined from 48.4% in 1996 to 49.9% in 2016. This urban expansion causes loss of vegetation cover that hinders the country’s regulation of retaining 60% forest according to The Constitution of the Kingdom of Bhutan. These finding can provide city planners and decision makers with information about the past and current spatial dynamics of LULC change to investigate, plan and monitor the urban development and management of Phuentsholing municipality.
Abstract: The rapid phase of urbanization and infrastructure development in Bhutan has been observed recently. This leads to causing of decrease in vegetation cover and growth in urban sprawl undergoing rapid land use/land cover change (LULC). This paper attempts to analyze the temporal and spatial patterns of LULC change and detects the urbanization process...
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Monitoring of Water Salinity of the Lower River Neretva (B&H)
Anita Ivanković,
Danijela Petrović,
Predrag Ivanković,
Jerina Majstorović
Issue:
Volume 2, Issue 6, November 2017
Pages:
136-143
Received:
16 November 2017
Accepted:
24 November 2017
Published:
3 January 2018
DOI:
10.11648/j.ijees.20170206.13
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Abstract: Water regime in the lower course of the Neretva River (Bosnia and Herzegovina) is very complex because of the downstream side impact and built hydropower system with the upstream side. Sea inflow into the aquifer and the surface flows of the valley depends on the amount of flow of fresh water from the basin. In the dry season, when inflows from the catchment reduced and longer duration, can not be drawn into the bed of the river in the form of salt 'wedge', and in the aquifer rises from deeper layers to the surface. This phenomenon extends deep upstream in the river valley. By measuring the physical (salinity, temperature, electrical conductivity) and chemical (amount of dissolved oxygen in water and pH) parameters at lower flow of the river Neretva (delta) water quality was determined with special attention to the occurrence of salinity. During the one-year monitoring were conducted field tests of physical-chemical parameters of the lower course of the Neretva river at 20 locations of significant testing maritime impacts on water quality. The physical parameters were measured temperature, conductivity and salinity, and the chemical quantity of dissolved oxygen, expressed as a percentage and mg L-1 in water and the pH value. The values of the above parameters were measured on the fild with combined meter WTW Multi-Parameter Instruments.
Abstract: Water regime in the lower course of the Neretva River (Bosnia and Herzegovina) is very complex because of the downstream side impact and built hydropower system with the upstream side. Sea inflow into the aquifer and the surface flows of the valley depends on the amount of flow of fresh water from the basin. In the dry season, when inflows from the...
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