This study reports the results of a pilot study on spatiotemporal characteristics of drivers’ vis... more This study reports the results of a pilot study on spatiotemporal characteristics of drivers’ visual behavior while driving in three different luminance levels in a tunnel. The study was carried out in a relatively long tunnel during the daytime. Six experienced drivers were recruited to participate in the driving experiment. Experimental data of pupil area and fixation point position (at the tunnel’s interior zone: 1566 m long) were collected by non-intrusive eye-tracking equipment at three luminance levels (2 cd/m2, 2.5 cd/m2, and 3 cd/m2). Fixation maps (color-coded maps presenting distributed data) were created based on fixation point position data to quantify changes in visual behavior. The results demonstrated that luminance levels had a significant effect on pupil areas and fixation zones. Fixation area and average pupil area had a significant negative correlation with luminance levels during the daytime. In addition, drivers concentrated more on the front road pavement, the ...
World Environmental and Water Resources Congress 2021, 2021
This paper presents the operational reliability assessment of a remotely controlled siphon system... more This paper presents the operational reliability assessment of a remotely controlled siphon system. The siphon system consists of water level switches, air vents, bilge pumps, etc. In this study, the reliability block diagram (RBD) model based on the ExtendSim software is applied to assess the operational reliability of a remotely-controlled siphon system. The Monte-Carlo simulation results from the RBD model demonstrate that the operational availability of the nonrepairable siphon system can be enhanced from 0.683 to 0.855 within a 1-year life cycle by increasing the redundancy for the vulnerable components, such as the water level switch and the air vent. The value can increase to 0.999 when adopting an on-site maintenance strategy. Based on the analysis of multiple scenarios and maintenance strategies, a suitable architecture of the siphon system is proposed herein.
Minimizing water consumption for producing hydropower is critical given that overuse of flows for... more Minimizing water consumption for producing hydropower is critical given that overuse of flows for energy production may result in a shortage of flows for other purposes such as irrigation and navigation. This paper presents a dimensional analysis for finding optimal flow discharge and optimal penstock diameter when designing impulse and reaction water turbines for hydropower systems. The objective of this analysis is to provide general insights for minimizing water consumption when producing hydropower. This analysis is based on the geometric and hydraulic characteristics of the penstock, the total hydraulic head, and the desired power production. As part of this analysis, various dimensionless relationships between power production, flow discharge, and head losses were derived. These relationships were used to draw general insights on determining optimal flow discharge and optimal penstock diameter. For instance, it was found that for minimizing water consumption, the ratio of head...
Tunnel lighting is the most significant component in total energy consumption in the whole infras... more Tunnel lighting is the most significant component in total energy consumption in the whole infrastructure. Hence, various lighting control strategies based on light-emitting diode (LED) technology have been investigated to conserve energy by decreasing luminaires’ operating time. In this study, four kinds of tunnel lighting control strategies and the development of their associated technologies are evaluated: no-control low-consumption lamps (LCL), time-scheduling control strategy (TSCS), daylight adaptation control strategy (DACS), and intelligent control strategy (ICS). This work investigates the relationship between initial investment and electrical costs as a function of tunnel length (L) and daily traffic volume (N) for the four control strategies. The analysis was performed using 100-day data collected in eleven Chinese tunnels. The tunnel length (L) ranged from 600 m to 3300 m and the daily traffic volume (N) ranged from 700 to 2500. The results showed that initial investment...
Wetlands play a significant role in flood mitigation. Remote sensing technologies as an efficient... more Wetlands play a significant role in flood mitigation. Remote sensing technologies as an efficient and accurate approach have been widely applied to delineate wetlands. Supervised classification is conventionally applied for remote sensing technologies to improve the wetland delineation accuracy. However, performing supervised classification requires preparing the training data, which is also considered time-consuming and prone to human mistakes. This paper presents a deterministic topographic wetland index to delineate wetland inundation areas without performing supervised classification. The classic methods such as Normalized Difference Vegetation Index, Normalized Difference Water Index, and Topographic Wetness Index were chosen to compare with the proposed deterministic topographic method on wetland delineation accuracy. The ground truth sample points validated by Google satellite imageries from four different years were used for the assessment of the delineation overall accuracy...
This paper presents a case study on the impact of dynamic management of wetland storage on downst... more This paper presents a case study on the impact of dynamic management of wetland storage on downstream ood control at the Cypress Creek Watershed in Houston, Texas. Dynamic storage management is performed by optimizing the schedule of ow releases from managed wetlands for minimizing downstream inundation. The main objective of this study is to compare the extent of downstream ood inundation with and without dynamic management of wetland storage. This study used HEC-HMS for the overland ows and the level pool routing in the wetlands and HEC-RAS for simulating river inundation. Wetlands were implemented in the midstream region of the watershed. The schedule of optimal wetland ow releases were determined using the MATLAB Genetic Algorithm toolbox. The optimization results indicate that, when wetland size exceeds a fairly low threshold, dynamic storage management of wetlands can signicantly reduce ood area, ood depth and ood duration at the downstream region of the watershed compared with the case without dynamic storage management.
This paper presents a case study on the impact of the size and location of wetlands on watershed-... more This paper presents a case study on the impact of the size and location of wetlands on watershed-scale ood control utilizing the Cypress Creek Watershed in Houston, Texas as the study area. Wetlands of dierent sizes were implemented at dierent locations (upstream, midstream, and downstream) of the watershed and corresponding hydrologic and hydraulic simulations were performed to investigate the impact that wetland size and location parameters have on downstream ood conditions. This study used HEC-HMS as the hydrologic model for the watershed, and HEC-RAS as the hydraulic model for rivers within the watershed. Wetlands were implemented in the HEC-HMS model as reservoirs. Simulation results indicate the more upstream wetlands are located within the watershed, the smaller the ood area, the shallower the ood depth, and the shorter the ood duration at the downstream region of the watershed. In addition, the downstream ood area, ood depth, and ood duration decrease as the size (storage capacity) of wetlands increases.
Mechanical strength and thermal properties may limit the usage of an electronic component in the ... more Mechanical strength and thermal properties may limit the usage of an electronic component in the high-tech industry. This paper investigated the influence of using CuO nanoparticles in a radial configuration microchannel of a disk from the mechanical and thermal points of view. In this regard, a disk under thermal and mechanical loading had been considered. The cooling setup consisted of a radial configuration microchannel with a constant fluid volume. Water was used as the base fluid and CuO particles were used as the coolant fluid. The results showed that the use of CuO nanoparticles would reduce the maximum disk temperature, the maximum thermal stress, and the maximum stress, as well as the maximum deformation on the body. The increasing number of channels would increase the maximum stress in the object as well. Another remarkable point was that increasing the nanoparticles did not necessarily lead to a more uniform heat distribution in the disk.
38th IAHR World Congress - "Water: Connecting the World", 2019
This paper reports a laboratory and numerical study on violent geysers in a vertical pipe. The la... more This paper reports a laboratory and numerical study on violent geysers in a vertical pipe. The laboratory geysers produced consists of a few consecutive violent eruptions within a time frame of a few seconds with heights that may exceed 30 m and with characteristics resembling geysers that occur in actual stormsewer systems (e.g., strongest eruption is not the first one but few eruptions later). In general, the present study shows that once the air pocket breaks through the free surface and produces a water spill, the horizontal pipe flow dynamics, in particular the rapidly changing pressure gradient following the first weak eruption, is driving the entire geyser mechanism. This conference paper is based on the following
A new luminance calculation method that accounts for mesopic vision and fog penetration ability i... more A new luminance calculation method that accounts for mesopic vision and fog penetration ability is presented. This method aims to select a suitable light source for street lighting and is obtained using the mesopic luminance calculation and transmittance calculation methods at each individual wavelength. Additionally, the new method was evaluated using six LED light sources between 3500 and 6000 K. Overall, the calculation results indicate that suitable LEDs’ CCT decreases with an increase of luminance for low transmittance rates. However, for high transmittance rates, high CCT LED lamps are the most suitable for street lighting. The recommended CCT of LED light sources for street lighting under different visibility and luminance conditions is presented.
This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a co... more This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a convective heating system with potential heating applications in the buildings sector. In an experimental study, characteristics of nanofluids were measured, including heat capacity, thermal conductivity, and density. The influences of mass flow rate and concentration of nanofluid on various parameters were quantified, such as pressure loss, friction coefficient, and heat transfer rate. For a concentration of 0.3 wt.%, the heat transfer increased by 46.3% and the pressure drop increased by 37.5%. The latter is due to the higher friction and viscosity of the bulk of the nanofluid. Although the pressure drop is higher, the thermo-hydraulic efficiency still increased by 19%. As a result, iron oxide (III)–therminol 66 presented reasonable thermal performance, higher heat transfer coefficient, and a lower pressure drop value (19% better performance in comparison with water) for the air–liquid c...
The early release from wetlands and shallow ponds could provide extra water storage during heavy ... more The early release from wetlands and shallow ponds could provide extra water storage during heavy rainfall, thus mitigating floods. In this paper, a remotely operated integrated siphon system intended to release water from wetlands/shallow ponds ahead of (a few hours or a few days before) a heavy rainfall that is forecasted to produce flooding is proposed. Siphons work under the pull of gravity and are limited to pond berm heights below about 6 m. An array (e.g. hundreds) of the proposed siphon system can be controlled remotely by an operator or by a Decision Support System. A self-operating and remotely controlled siphon system could open the doors for managing wetlands and shallow ponds for multiple purposes, including flood control and improvement of aquatic habitat. Laboratory tests using 4 and 15 cm-diameter siphons were performed in this study. The results showed that the integrated control system is technically feasible and economically viable. INDEX TERMS Flood mitigation, remote control, smart wetland, water storage management system.
In this article, a thermodynamic study was conducted on the energetic and exergy performance of a... more In this article, a thermodynamic study was conducted on the energetic and exergy performance of a new configuration of liquid chemical looping gasification (LCLG) plant integrated with a power block to assess the overall performance of the system including exergy partitioned in syngas and first law efficiency (FLE). LCLG is a relatively new concept for the production of high-quality synthetic gas from solid feedstock such as biomass. As the temperature and pressure of the looping system are high, there is thermodynamic potential to co-produce chemical products, power and heat. Hence, in the present work, three different configurations of a power cycle were thermodynamically assessed. In the first proposed power cycle, the produced syngas from the gasifier was combusted in a combustion chamber and the exhausted gases were fed into a gas turbine. In the second and third proposed power cycles, the hot air was directly fed into a gas turbine or was used to produce steam for the steam tu...
This paper reports a laboratory study on violent geysers in a vertical pipe. Each geyser produced... more This paper reports a laboratory study on violent geysers in a vertical pipe. Each geyser produced consists of a few consecutive violent eruptions within a time frame of a few seconds with heights that may exceed 30 m. Herein, the term violent is used to distinguish the present work from previous studies, which reported geyser heights that were relatively small compared to the present study. Previous work has speculated that the extreme behavior of geysers is driven by the buoyant rise of the air pocket in the vertical pipe. The present study shows that once the air pocket breaks through the free surface and produces a water spill, the horizontal pipe ow dynamics, in particular the rapidly changing pressure gradient following the rst weak eruption, is driving the entire geyser mechanism.
This paper presents an intelligent control method for tunnel lighting based on traffic volume. Th... more This paper presents an intelligent control method for tunnel lighting based on traffic volume. The monitoring data for a period of 12 days of the Chibai tunnel (located in the Jilin province of China) under different weather conditions was selected as the case study. The data used in the analysis included traffic volume, vehicle speed, the time of light-emitting diodes (LEDs) operating at their lowest luminance level, and the average time interval between two consecutive vehicles. The traffic flow analysis indicated that the tunnel has a relatively heavy traffic volume in the daytime (7:00 a.m. to 6:00 p.m.) and a relatively low traffic volume in the nighttime (12:00 a.m. to 6:00 a.m. and 7:00 p.m. to 12:00 a.m.). Thus, we propose a tunnel lighting control method that distinguishes day and night operational strategies. In the daytime, the luminance of tunnel zones depends on tunnel exterior luminance, traffic volume and vehicle speed regardless of vehicle presence. In the night, the "vehicle in, light brightens; vehicle out, light darkens" control method is adopted for the tunnel luminance, which depends on vehicle presence.
International journal of environmental research and public health, Jan 2, 2018
The aim of this study was to investigate how vehicle speed influences the characteristics of driv... more The aim of this study was to investigate how vehicle speed influences the characteristics of driver's eye movement at highway tunnel entrances during day and night. In this study, six drivers' eye movement data (from 200 m before tunnel entrance to 200 m inside tunnel entrance) under five predetermined vehicle speeds (40, 50, 60, 70 and 80 km/h) in the daytime and three predetermined vehicle speeds (40, 60 and 80 km/h) in the nighttime were recorded using the non-intrusive Dikablis Professional eye-tracking system. Pupil size, the average fixation duration time and the average number of fixation were analyzed and then the influence of the vehicle speed on these parameters was evaluated by means of IBM SPSS Statistics 20.0. The results for pupil size in daytime increased when approaching the tunnel entrance, while as for nighttime, pupil size decreased when approaching the tunnel entrance and then increased after entering the tunnel. The pupil size in daytime has a significan...
This paper presents a dimensional analysis for determining optimal flow discharge and optimal pen... more This paper presents a dimensional analysis for determining optimal flow discharge and optimal penstock diameter when designing impulse and reaction turbines for hydropower systems. The aim of this analysis is to provide general insights for minimizing water consumption when producing hydropower. This analysis is based on the geometric and hydraulic characteristics of the penstock, the total hydraulic head and the desired power production. As part of this analysis, various dimensionless relationships between power production, flow discharge and head losses were derived. These relationships were used to withdraw general insights on determining optimal flow discharge and optimal penstock diameter. For instance, it was found that for minimizing water consumption, the ratio of head loss to gross head should not exceed about 15%. Two examples of application are presented to illustrate the procedure for determining optimal flow discharge and optimal penstock diameter for impulse and reaction turbines.
The U.S. Army Corps of Engineers' Hydrologic Engineering Center's River Analysis System (HEC-RAS)... more The U.S. Army Corps of Engineers' Hydrologic Engineering Center's River Analysis System (HEC-RAS) is a widely used software application for performing one-dimensional and two-dimensional steady and unsteady flow river hydraulics calculations, sediment transport-mobile bed modeling, and water quality analysis. User's of HEC-RAS have often unique applications including the coupling with other software to perform system analysis such as optimization of flooding structures and multi-objective reservoir operation under uncertainty. One state-of-the-art environment for integrating software is MATLAB, which integrates computation, visualization, and programming in an easy-to-use environment. This paper presents a set of MATLAB scripts to write input files, read output files, make plots, execute parallel computations, and perform fully-automated functions of HEC-RAS. Examples of procedures are presented throughout the paper and they are illustrated using a river-reservoir network that involves ten inline structures (e.g., dams) with operation of gates at each of these dams.
Most dams built for flood control are operated based on rule curves, which are determined based o... more Most dams built for flood control are operated based on rule curves, which are determined based on annual estimates of system loads, reservoir storages and resources provided by stakeholders. Rule curves neglect the flow dynamics in the entire river system, which makes this approach a “slow-response” method for flood control. This is particularly true in complex river systems when parts of the river system may have enough in-line storage capacity, while other portions of the system may be overflowing. Clearly, rule curves are insufficient for ...
This study reports the results of a pilot study on spatiotemporal characteristics of drivers’ vis... more This study reports the results of a pilot study on spatiotemporal characteristics of drivers’ visual behavior while driving in three different luminance levels in a tunnel. The study was carried out in a relatively long tunnel during the daytime. Six experienced drivers were recruited to participate in the driving experiment. Experimental data of pupil area and fixation point position (at the tunnel’s interior zone: 1566 m long) were collected by non-intrusive eye-tracking equipment at three luminance levels (2 cd/m2, 2.5 cd/m2, and 3 cd/m2). Fixation maps (color-coded maps presenting distributed data) were created based on fixation point position data to quantify changes in visual behavior. The results demonstrated that luminance levels had a significant effect on pupil areas and fixation zones. Fixation area and average pupil area had a significant negative correlation with luminance levels during the daytime. In addition, drivers concentrated more on the front road pavement, the ...
World Environmental and Water Resources Congress 2021, 2021
This paper presents the operational reliability assessment of a remotely controlled siphon system... more This paper presents the operational reliability assessment of a remotely controlled siphon system. The siphon system consists of water level switches, air vents, bilge pumps, etc. In this study, the reliability block diagram (RBD) model based on the ExtendSim software is applied to assess the operational reliability of a remotely-controlled siphon system. The Monte-Carlo simulation results from the RBD model demonstrate that the operational availability of the nonrepairable siphon system can be enhanced from 0.683 to 0.855 within a 1-year life cycle by increasing the redundancy for the vulnerable components, such as the water level switch and the air vent. The value can increase to 0.999 when adopting an on-site maintenance strategy. Based on the analysis of multiple scenarios and maintenance strategies, a suitable architecture of the siphon system is proposed herein.
Minimizing water consumption for producing hydropower is critical given that overuse of flows for... more Minimizing water consumption for producing hydropower is critical given that overuse of flows for energy production may result in a shortage of flows for other purposes such as irrigation and navigation. This paper presents a dimensional analysis for finding optimal flow discharge and optimal penstock diameter when designing impulse and reaction water turbines for hydropower systems. The objective of this analysis is to provide general insights for minimizing water consumption when producing hydropower. This analysis is based on the geometric and hydraulic characteristics of the penstock, the total hydraulic head, and the desired power production. As part of this analysis, various dimensionless relationships between power production, flow discharge, and head losses were derived. These relationships were used to draw general insights on determining optimal flow discharge and optimal penstock diameter. For instance, it was found that for minimizing water consumption, the ratio of head...
Tunnel lighting is the most significant component in total energy consumption in the whole infras... more Tunnel lighting is the most significant component in total energy consumption in the whole infrastructure. Hence, various lighting control strategies based on light-emitting diode (LED) technology have been investigated to conserve energy by decreasing luminaires’ operating time. In this study, four kinds of tunnel lighting control strategies and the development of their associated technologies are evaluated: no-control low-consumption lamps (LCL), time-scheduling control strategy (TSCS), daylight adaptation control strategy (DACS), and intelligent control strategy (ICS). This work investigates the relationship between initial investment and electrical costs as a function of tunnel length (L) and daily traffic volume (N) for the four control strategies. The analysis was performed using 100-day data collected in eleven Chinese tunnels. The tunnel length (L) ranged from 600 m to 3300 m and the daily traffic volume (N) ranged from 700 to 2500. The results showed that initial investment...
Wetlands play a significant role in flood mitigation. Remote sensing technologies as an efficient... more Wetlands play a significant role in flood mitigation. Remote sensing technologies as an efficient and accurate approach have been widely applied to delineate wetlands. Supervised classification is conventionally applied for remote sensing technologies to improve the wetland delineation accuracy. However, performing supervised classification requires preparing the training data, which is also considered time-consuming and prone to human mistakes. This paper presents a deterministic topographic wetland index to delineate wetland inundation areas without performing supervised classification. The classic methods such as Normalized Difference Vegetation Index, Normalized Difference Water Index, and Topographic Wetness Index were chosen to compare with the proposed deterministic topographic method on wetland delineation accuracy. The ground truth sample points validated by Google satellite imageries from four different years were used for the assessment of the delineation overall accuracy...
This paper presents a case study on the impact of dynamic management of wetland storage on downst... more This paper presents a case study on the impact of dynamic management of wetland storage on downstream ood control at the Cypress Creek Watershed in Houston, Texas. Dynamic storage management is performed by optimizing the schedule of ow releases from managed wetlands for minimizing downstream inundation. The main objective of this study is to compare the extent of downstream ood inundation with and without dynamic management of wetland storage. This study used HEC-HMS for the overland ows and the level pool routing in the wetlands and HEC-RAS for simulating river inundation. Wetlands were implemented in the midstream region of the watershed. The schedule of optimal wetland ow releases were determined using the MATLAB Genetic Algorithm toolbox. The optimization results indicate that, when wetland size exceeds a fairly low threshold, dynamic storage management of wetlands can signicantly reduce ood area, ood depth and ood duration at the downstream region of the watershed compared with the case without dynamic storage management.
This paper presents a case study on the impact of the size and location of wetlands on watershed-... more This paper presents a case study on the impact of the size and location of wetlands on watershed-scale ood control utilizing the Cypress Creek Watershed in Houston, Texas as the study area. Wetlands of dierent sizes were implemented at dierent locations (upstream, midstream, and downstream) of the watershed and corresponding hydrologic and hydraulic simulations were performed to investigate the impact that wetland size and location parameters have on downstream ood conditions. This study used HEC-HMS as the hydrologic model for the watershed, and HEC-RAS as the hydraulic model for rivers within the watershed. Wetlands were implemented in the HEC-HMS model as reservoirs. Simulation results indicate the more upstream wetlands are located within the watershed, the smaller the ood area, the shallower the ood depth, and the shorter the ood duration at the downstream region of the watershed. In addition, the downstream ood area, ood depth, and ood duration decrease as the size (storage capacity) of wetlands increases.
Mechanical strength and thermal properties may limit the usage of an electronic component in the ... more Mechanical strength and thermal properties may limit the usage of an electronic component in the high-tech industry. This paper investigated the influence of using CuO nanoparticles in a radial configuration microchannel of a disk from the mechanical and thermal points of view. In this regard, a disk under thermal and mechanical loading had been considered. The cooling setup consisted of a radial configuration microchannel with a constant fluid volume. Water was used as the base fluid and CuO particles were used as the coolant fluid. The results showed that the use of CuO nanoparticles would reduce the maximum disk temperature, the maximum thermal stress, and the maximum stress, as well as the maximum deformation on the body. The increasing number of channels would increase the maximum stress in the object as well. Another remarkable point was that increasing the nanoparticles did not necessarily lead to a more uniform heat distribution in the disk.
38th IAHR World Congress - "Water: Connecting the World", 2019
This paper reports a laboratory and numerical study on violent geysers in a vertical pipe. The la... more This paper reports a laboratory and numerical study on violent geysers in a vertical pipe. The laboratory geysers produced consists of a few consecutive violent eruptions within a time frame of a few seconds with heights that may exceed 30 m and with characteristics resembling geysers that occur in actual stormsewer systems (e.g., strongest eruption is not the first one but few eruptions later). In general, the present study shows that once the air pocket breaks through the free surface and produces a water spill, the horizontal pipe flow dynamics, in particular the rapidly changing pressure gradient following the first weak eruption, is driving the entire geyser mechanism. This conference paper is based on the following
A new luminance calculation method that accounts for mesopic vision and fog penetration ability i... more A new luminance calculation method that accounts for mesopic vision and fog penetration ability is presented. This method aims to select a suitable light source for street lighting and is obtained using the mesopic luminance calculation and transmittance calculation methods at each individual wavelength. Additionally, the new method was evaluated using six LED light sources between 3500 and 6000 K. Overall, the calculation results indicate that suitable LEDs’ CCT decreases with an increase of luminance for low transmittance rates. However, for high transmittance rates, high CCT LED lamps are the most suitable for street lighting. The recommended CCT of LED light sources for street lighting under different visibility and luminance conditions is presented.
This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a co... more This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a convective heating system with potential heating applications in the buildings sector. In an experimental study, characteristics of nanofluids were measured, including heat capacity, thermal conductivity, and density. The influences of mass flow rate and concentration of nanofluid on various parameters were quantified, such as pressure loss, friction coefficient, and heat transfer rate. For a concentration of 0.3 wt.%, the heat transfer increased by 46.3% and the pressure drop increased by 37.5%. The latter is due to the higher friction and viscosity of the bulk of the nanofluid. Although the pressure drop is higher, the thermo-hydraulic efficiency still increased by 19%. As a result, iron oxide (III)–therminol 66 presented reasonable thermal performance, higher heat transfer coefficient, and a lower pressure drop value (19% better performance in comparison with water) for the air–liquid c...
The early release from wetlands and shallow ponds could provide extra water storage during heavy ... more The early release from wetlands and shallow ponds could provide extra water storage during heavy rainfall, thus mitigating floods. In this paper, a remotely operated integrated siphon system intended to release water from wetlands/shallow ponds ahead of (a few hours or a few days before) a heavy rainfall that is forecasted to produce flooding is proposed. Siphons work under the pull of gravity and are limited to pond berm heights below about 6 m. An array (e.g. hundreds) of the proposed siphon system can be controlled remotely by an operator or by a Decision Support System. A self-operating and remotely controlled siphon system could open the doors for managing wetlands and shallow ponds for multiple purposes, including flood control and improvement of aquatic habitat. Laboratory tests using 4 and 15 cm-diameter siphons were performed in this study. The results showed that the integrated control system is technically feasible and economically viable. INDEX TERMS Flood mitigation, remote control, smart wetland, water storage management system.
In this article, a thermodynamic study was conducted on the energetic and exergy performance of a... more In this article, a thermodynamic study was conducted on the energetic and exergy performance of a new configuration of liquid chemical looping gasification (LCLG) plant integrated with a power block to assess the overall performance of the system including exergy partitioned in syngas and first law efficiency (FLE). LCLG is a relatively new concept for the production of high-quality synthetic gas from solid feedstock such as biomass. As the temperature and pressure of the looping system are high, there is thermodynamic potential to co-produce chemical products, power and heat. Hence, in the present work, three different configurations of a power cycle were thermodynamically assessed. In the first proposed power cycle, the produced syngas from the gasifier was combusted in a combustion chamber and the exhausted gases were fed into a gas turbine. In the second and third proposed power cycles, the hot air was directly fed into a gas turbine or was used to produce steam for the steam tu...
This paper reports a laboratory study on violent geysers in a vertical pipe. Each geyser produced... more This paper reports a laboratory study on violent geysers in a vertical pipe. Each geyser produced consists of a few consecutive violent eruptions within a time frame of a few seconds with heights that may exceed 30 m. Herein, the term violent is used to distinguish the present work from previous studies, which reported geyser heights that were relatively small compared to the present study. Previous work has speculated that the extreme behavior of geysers is driven by the buoyant rise of the air pocket in the vertical pipe. The present study shows that once the air pocket breaks through the free surface and produces a water spill, the horizontal pipe ow dynamics, in particular the rapidly changing pressure gradient following the rst weak eruption, is driving the entire geyser mechanism.
This paper presents an intelligent control method for tunnel lighting based on traffic volume. Th... more This paper presents an intelligent control method for tunnel lighting based on traffic volume. The monitoring data for a period of 12 days of the Chibai tunnel (located in the Jilin province of China) under different weather conditions was selected as the case study. The data used in the analysis included traffic volume, vehicle speed, the time of light-emitting diodes (LEDs) operating at their lowest luminance level, and the average time interval between two consecutive vehicles. The traffic flow analysis indicated that the tunnel has a relatively heavy traffic volume in the daytime (7:00 a.m. to 6:00 p.m.) and a relatively low traffic volume in the nighttime (12:00 a.m. to 6:00 a.m. and 7:00 p.m. to 12:00 a.m.). Thus, we propose a tunnel lighting control method that distinguishes day and night operational strategies. In the daytime, the luminance of tunnel zones depends on tunnel exterior luminance, traffic volume and vehicle speed regardless of vehicle presence. In the night, the "vehicle in, light brightens; vehicle out, light darkens" control method is adopted for the tunnel luminance, which depends on vehicle presence.
International journal of environmental research and public health, Jan 2, 2018
The aim of this study was to investigate how vehicle speed influences the characteristics of driv... more The aim of this study was to investigate how vehicle speed influences the characteristics of driver's eye movement at highway tunnel entrances during day and night. In this study, six drivers' eye movement data (from 200 m before tunnel entrance to 200 m inside tunnel entrance) under five predetermined vehicle speeds (40, 50, 60, 70 and 80 km/h) in the daytime and three predetermined vehicle speeds (40, 60 and 80 km/h) in the nighttime were recorded using the non-intrusive Dikablis Professional eye-tracking system. Pupil size, the average fixation duration time and the average number of fixation were analyzed and then the influence of the vehicle speed on these parameters was evaluated by means of IBM SPSS Statistics 20.0. The results for pupil size in daytime increased when approaching the tunnel entrance, while as for nighttime, pupil size decreased when approaching the tunnel entrance and then increased after entering the tunnel. The pupil size in daytime has a significan...
This paper presents a dimensional analysis for determining optimal flow discharge and optimal pen... more This paper presents a dimensional analysis for determining optimal flow discharge and optimal penstock diameter when designing impulse and reaction turbines for hydropower systems. The aim of this analysis is to provide general insights for minimizing water consumption when producing hydropower. This analysis is based on the geometric and hydraulic characteristics of the penstock, the total hydraulic head and the desired power production. As part of this analysis, various dimensionless relationships between power production, flow discharge and head losses were derived. These relationships were used to withdraw general insights on determining optimal flow discharge and optimal penstock diameter. For instance, it was found that for minimizing water consumption, the ratio of head loss to gross head should not exceed about 15%. Two examples of application are presented to illustrate the procedure for determining optimal flow discharge and optimal penstock diameter for impulse and reaction turbines.
The U.S. Army Corps of Engineers' Hydrologic Engineering Center's River Analysis System (HEC-RAS)... more The U.S. Army Corps of Engineers' Hydrologic Engineering Center's River Analysis System (HEC-RAS) is a widely used software application for performing one-dimensional and two-dimensional steady and unsteady flow river hydraulics calculations, sediment transport-mobile bed modeling, and water quality analysis. User's of HEC-RAS have often unique applications including the coupling with other software to perform system analysis such as optimization of flooding structures and multi-objective reservoir operation under uncertainty. One state-of-the-art environment for integrating software is MATLAB, which integrates computation, visualization, and programming in an easy-to-use environment. This paper presents a set of MATLAB scripts to write input files, read output files, make plots, execute parallel computations, and perform fully-automated functions of HEC-RAS. Examples of procedures are presented throughout the paper and they are illustrated using a river-reservoir network that involves ten inline structures (e.g., dams) with operation of gates at each of these dams.
Most dams built for flood control are operated based on rule curves, which are determined based o... more Most dams built for flood control are operated based on rule curves, which are determined based on annual estimates of system loads, reservoir storages and resources provided by stakeholders. Rule curves neglect the flow dynamics in the entire river system, which makes this approach a “slow-response” method for flood control. This is particularly true in complex river systems when parts of the river system may have enough in-line storage capacity, while other portions of the system may be overflowing. Clearly, rule curves are insufficient for ...
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Papers by Arturo S Leon