Lagrangian block hydrodynamics of macro resistance in a river-flow model

River hydrodynamicsBed roughness and flow resistanc

Flood Wave Dynamics Using Lagrangian Block Advection

Flood wave dynamics are determined by a robust and accurate Lagrangian block advection (LBA) scheme that can track the dry-and-wet interface and capture the shocks without using any slope limiter to control the numerical oscillations. Two series of challenging numerical problems are considered using the LBA. First, computations are carried out for water waves in a parabolic bowl. The wetting-and-drying interface on the surface of the bowl is tracked by the LBA method with absolute computational stability. The accuracy of the LBA method is verified by the convergent of the numerical solution to an exact solution. Finally, the LBA method is applied to carry out a series of flood wave simulations, which have closely reproduced the data obtained from the laboratory experiments. &nbsp

Trend Analysis of Tides Level and Projection Sea Level Rise On the West Coast of Peninsular Malaysia

Globally, sea levels are rising due to climate change caused by humans. Current and future sea level rise will have a variety of effects, particularly on coastal infrastructure. This study analysed the tidal level trend and projected sea level rise along the western coast of peninsular Malaysia using tide level records collected between 1986 and 2012. The seasonal Mann-Kendall test and linear trend were used to determine the tide level trend over time and to predict sea level rise for 2050 and 2100. Based on a confidence interval of 95%, the results of the analysis indicated a rising trend at all stations. Tau values for the Mann-Kendall test range between 0.16 and 0.33, while seasonal Mann-Kendall values range between 0.18 and 0.41. Based on the sea level projection analysis, the mean sea level will rise between 8.77 cm and 14.29 cm in 2050, and between 20.44 cm and 33.20 cm in 2100. In conclusion, the sea level trend at all stations on the west coasts of peninsular Malaysia exhibits an upward trend

Trend Analysis of Tides Level and Projection Sea Level Rise On the West Coast of Peninsular Malaysia

Globally, sea levels are rising due to climate change caused by humans. Current and future sea level rise will have a variety of effects, particularly on coastal infrastructure. This study analysed the tidal level trend and projected sea level rise along the western coast of peninsular Malaysia using tide level records collected between 1986 and 2012. The seasonal Mann-Kendall test and linear trend were used to determine the tide level trend over time and to predict sea level rise for 2050 and 2100. Based on a confidence interval of 95%, the results of the analysis indicated a rising trend at all stations. Tau values for the Mann-Kendall test range between 0.16 and 0.33, while seasonal Mann-Kendall values range between 0.18 and 0.41. Based on the sea level projection analysis, the mean sea level will rise between 8.77 cm and 14.29 cm in 2050, and between 20.44 cm and 33.20 cm in 2100. In conclusion, the sea level trend at all stations on the west coasts of peninsular Malaysia exhibits an upward trend

Hematopoietic cell differentiation from embryonic and induced pluripotent stem cells

Pluripotent stem cells, both embryonic stem cells and induced pluripotent stem cells, are undifferentiated cells that can self-renew and potentially differentiate into all hematopoietic lineages, such as hematopoietic stem cells (HSCs), hematopoietic progenitor cells and mature hematopoietic cells in the presence of a suitable culture system. Establishment of pluripotent stem cells provides a comprehensive model to study early hematopoietic development and has emerged as a powerful research tool to explore regenerative medicine. Nowadays, HSC transplantation and hematopoietic cell transfusion have successfully cured some patients, especially in malignant hematological diseases. Owing to a shortage of donors and a limited number of the cells, hematopoietic cell induction from pluripotent stem cells has been regarded as an alternative source of HSCs and mature hematopoietic cells for intended therapeutic purposes. Pluripotent stem cells are therefore extensively utilized to facilitate better understanding in hematopoietic development by recapitulating embryonic development in vivo, in which efficient strategies can be easily designed and deployed for the generation of hematopoietic lineages in vitro. We hereby review the current progress of hematopoietic cell induction from embryonic stem/induced pluripotent stem cells

Flood Mitigation Approaches: Selected Cases Across Europe, Oceania and Asia

Flood is natural phenomenon that cannot be completely controlled by man. Flood is a global problem. Even urban areas which have good development planning and drainage systems are susceptible to floods. Flooding in urban area is usually associated with poor drainage system maintenance, failure to plan drainage system, area development is not planned properly, and climate change factors. Typically, engineering measures are meant to reduce severity of flood problems and they are quite costly. Goal of this paper is to assess the various mitigation approaches that have been used to mitigate floods across Europe, Oceania and Asia continents. Selected case studies involving the North Sea flood, as well as floods in the Netherlands, Scotland, New Zealand, Australia, Hong Kong, Taiwan, Singapore and Malaysia were considered. Approaches that were highlighted include construction of dam, breakwater, canal, and pumping system. It has also been found that flood solution methods by way of source control is not so popular to be fully practiced. Hence, the sustainability of good development is actually a solution to problem of flooding, especially to mitigate flash floods that often occur in an urban areas

Rainfall-Runoff Response of A Suburban Area

Batu Pahat experiences flash floods whenever intense rainfall coincides with high tide. Among the factors which cause flash floods are due to Batu Pahat river catchment's flat and low-lying geographical features as well as high-intensity rainfall. The goals of the study are to analyse the frequency of rainfall events for SMK Munshi Sulaiman station and to investigate runoff due to severe rainfall events within the study area. The observed daily rainfall depth record between 2010 and 2021 was obtained from the Department of Irrigation and Drainage (DID) Malaysia. The frequency of rainfall events within the 11-year period is examined using empirical rainfall intensity formulation. Rainfall-runoff of the five most heavy rainfall events in 2021 within the study area are simulated using HEC-HMS. It has been found that most daily rainfall events have a frequency of a 1-year return period. Only three events were found to have a return period of up to 2-year ARI, with a maximum rainfall depth of 110.67 mm. Five heaviest rainfall events in 2021 were obtained from DID's real-time online platform for rainfall-runoff simulations. One of the events, which occurred in June 2021 has a frequency larger than a 100-year return period while other events have return periods ranging from 1-year to 5-year. Simulations produced by HEC-HMS for these events in January, April, May, June, and September 2021 have resulted in peak flow of 6.7 m3/s, 26.8 m3/s, 24.7 m3/s, 39.9 m3/s, and 39.9 m3/s, respectively. Based on frequency analysis, rainfall-runoff simulations, and field observations, it can be concluded that flash floods are highly possible due to high-intensity rainfall as well as lowland topographical features of the study area. Therefore, flood mitigation measures need to be carried out to improve the drainage system for the suburban area

Tidal Effect on Coastal Municipal Drainage System: Case Study of Bandar Maharani, Muar

Flash flood at Bandar Maharani, Muar is a common occurrence. Although, numerous studies and continual improvement to drainage systems have been carried out, flash flood at Bandar Maharani still persists. Aim of this study is to assess tidal effect on effectiveness of Bandar Maharani drainage system. 80% of the 12.25 km area of Bandar Maharani consists of residentials and commercial buildings. Capacity of drainage system along 15 major roads in Bandar Maharani has been evaluated. Peak flows due to 5, 10, 50 and 100-year ARI rainfall were considered. High tide which occurred in 1999 has been used to investigate the effect of tides on capacity of drain along Jalan Bakri. It has been shown that high tide has reduced as much as 32% of capacity of drains along Jalan Bakri, a major drainage system of Bandar Maharani. The effect of tides can reach as far as 3.687 km upstream. This means that when high tides and heavy rain occur concurrently, capacity of drains along Jalan Bakri will be affected, thus lead to flash floods

Tidal Effect on Coastal Municipal Drainage System: Case Study of Bandar Maharani, Muar

Flash flood at Bandar Maharani, Muar is a common occurrence. Although, numerous studies and continual improvement to drainage systems have been carried out, flash flood at Bandar Maharani still persists. Aim of this study is to assess tidal effect on effectiveness of Bandar Maharani drainage system. 80% of the 12.25 km area of Bandar Maharani consists of residentials and commercial buildings. Capacity of drainage system along 15 major roads in Bandar Maharani has been evaluated. Peak flows due to 5, 10, 50 and 100-year ARI rainfall were considered. High tide which occurred in 1999 has been used to investigate the effect of tides on capacity of drain along Jalan Bakri. It has been shown that high tide has reduced as much as 32% of capacity of drains along Jalan Bakri, a major drainage system of Bandar Maharani. The effect of tides can reach as far as 3.687 km upstream. This means that when high tides and heavy rain occur concurrently, capacity of drains along Jalan Bakri will be affected, thus lead to flash floods

Rainfall-Runoff Response of A Suburban Area

Batu Pahat experiences flash floods whenever intense rainfall coincides with high tide. Among the factors which cause flash floods are due to Batu Pahat river catchment's flat and low-lying geographical features as well as high-intensity rainfall. The goals of the study are to analyse the frequency of rainfall events for SMK Munshi Sulaiman station and to investigate runoff due to severe rainfall events within the study area. The observed daily rainfall depth record between 2010 and 2021 was obtained from the Department of Irrigation and Drainage (DID) Malaysia. The frequency of rainfall events within the 11-year period is examined using empirical rainfall intensity formulation. Rainfall-runoff of the five most heavy rainfall events in 2021 within the study area are simulated using HEC-HMS. It has been found that most daily rainfall events have a frequency of a 1-year return period. Only three events were found to have a return period of up to 2-year ARI, with a maximum rainfall depth of 110.67 mm. Five heaviest rainfall events in 2021 were obtained from DID's real-time online platform for rainfall-runoff simulations. One of the events, which occurred in June 2021 has a frequency larger than a 100-year return period while other events have return periods ranging from 1-year to 5-year. Simulations produced by HEC-HMS for these events in January, April, May, June, and September 2021 have resulted in peak flow of 6.7 m3/s, 26.8 m3/s, 24.7 m3/s, 39.9 m3/s, and 39.9 m3/s, respectively. Based on frequency analysis, rainfall-runoff simulations, and field observations, it can be concluded that flash floods are highly possible due to high-intensity rainfall as well as lowland topographical features of the study area. Therefore, flood mitigation measures need to be carried out to improve the drainage system for the suburban area