Renewable & Sustainable Energy Reviews, Sep 1, 2017
One of the most abundant energy sources exists in this world is the ocean wave energy. By far, it... more One of the most abundant energy sources exists in this world is the ocean wave energy. By far, it has shown to be the most clean, renewable, predicted energy and has raised the potential to compete with the current use of nonrenewable energy sources. Recent research conducted on wave energy invention has opened a new dimension to slowly reduce the dependency on fossil fuel by introducing new technology on the renewable world but relatively lacking in economical aspect. This review brings the latest status on integration of wave energy device with other marine facilities, which is the breakwater structure that may possibly aid to cost sharing. Most researches done on this field highlighted countries experiencing rough sea condition and focused less on countries with medium wave condition as faced by the Asian continent. The potential for energy extraction and wave dissipation for medium wave condition will be discussed in this review by considering several aspects including reliability, effectiveness and performance. Finally, this review shows that the integration opens up a new dimension to acknowledge the technology harnessing ocean wave, especially for the Asian countries experiencing medium wave condition.
This paper describes the implementation of a PIC microcontroller in a conventional laboratory-typ... more This paper describes the implementation of a PIC microcontroller in a conventional laboratory-type electronic trainer. The work comprises software for the PIC and hardware for the software. The PIC controller uses an EasyPIC-6 board and includes a PC-interfaced programmer for the PIC chip. It has many external modules: 128 × 64 graphic LCD display, 2 × 16 LCD display, 4 × 4 keypad, and port expander, all in the same bench. The trainer is capable of 36 experiments in logic/analogue electronic and control systems. A 5-sided approximate sensor, two photoelectric sensors (BR56-DDT-P and BEN9M-TFR), four CMOS, four BCD-7-segment driven by CD4511B, two relays (2-pole and 3-pole), six voltages, ammeter measurement, DC motor, and 24VDC power supply, connect through connectors and pinions. Results of all the experiments show the trainer satisfying requirements of undergraduate and postgraduate projects involving conventional electronic and classical control systems.
The present article illustrates the modeling and optimization of a dual-slot waveguide for the ap... more The present article illustrates the modeling and optimization of a dual-slot waveguide for the application of a refractive index biosensor. The nanometer scale waveguide structure uses the silicon-on-insulator platform for the consideration of higher sensitivity and compactness of a resonator biosensor. The modal analysis is performed using the finite difference method based on full vector eigenmode calculation. The maximum field penetration in the lower index region is found for the quasi-TE mode. The sensitivity is maximized through the optimization of the waveguide dimension by relating effective refractive index with the dispersion of a waveguide. The biosensor showed the maximum calculated sensitivity of 461.327 nm/RIU and a limit-of-detection of 2.601 × 10-6 RIU (where RIU denotes refractive index unit).
International journal of innovative technology and exploring engineering, Oct 30, 2019
Multistage-overtopping wave energy device is an example of the overtopping concept in extracting ... more Multistage-overtopping wave energy device is an example of the overtopping concept in extracting energy from the ocean wave. The multistage opening allows the wave to overtop and stored inside the multistage reservoirs and later used for electricity generation. Previously, using concentrated V-shape-ramp on the conventional multi-reservoir Sea Slot-Cone Generator (SSG) has been proven to improve up to 67 percent in hydraulic power at the 3.5 meters of significant wave height and 9.3 meters of wave period. However, the performance begins to drop when operating at smaller wave height consisting of 2.5-meter significant wave height and 7.9 seconds of wave period. Thus, this follow-up paper presents a numerical study to improve device performance, especially at small wave height. Five breakwater-ramp designs were tested consisting of Basis, Design 1 to Design 5. The overtopping device performance was simulated using FLOW-3D CFD software. Results are presented in the form of mean overtopping discharge or potential energy stored and the total energy potential for each propose breakwater-ramp design. The numerical results show that the highest total energy potential represents as the potential power output is recorded by Design 4 and Design 5 with 63.26 and 63.05 kW respectively, compared to basis SSG device with only 29.14 kW at the wave height of 2.8 meters and a wave period of 9.3 seconds.
The aim of our paper is to study the effects of roll motion on a transverse stability of a small ... more The aim of our paper is to study the effects of roll motion on a transverse stability of a small boat. Roll frequency will be calculated and analyzed for reducing motion sickness based on stabilit solution of ship roll motion will be also investigated in our paper.
This study suggests a new approach for the reduction of fuel consumption and CO2 emission with th... more This study suggests a new approach for the reduction of fuel consumption and CO2 emission with the assist of renewable energy. The focus of the study is the adaptation of wind power electrical generating system onboard. The electricity generated from wind is believed able to help reduce the fuel oil consumption and CO2 emission. A product oil tanker has been selected for the case study. The route of study is the round trip from Singapore to Jeddah and Taichung to Singapore. Wind power generation is calculated based on available of wind data along the routes. Economic assessment has been carried out to assess the feasibility of investment in this project. With the use of simple payback method, the result shows that investment cost will be repaid within 10 years. Besides, Net Present Value indicates a positive value within an investment period of 16 years by 10% internal rate of return. The installation of the system onboard gives a significant reduction in fuel oil consumption and CO2 emission. A 38.69% of saving can be achieved in a year for vessels which travel through the selected routes of study in normal sea going condition. Keywords : Wind turbine; green energy; FO and CO2 emission reduction
Wake wash has become a significant issue in the ship design industry due to its impact on the env... more Wake wash has become a significant issue in the ship design industry due to its impact on the environment in terms of erosion of natural shoreline wetlands. Many ideas for reducing wake wash have been introduced. This research work presents the development of a low wake wash catamaran hull form. In particular, the study is focused on the effectiveness of specially designed fin in order to reduce the wake wash produced by the ship. The fin was attached vertically along the centerline of the catamaran model and the model was tested in the towing tank of Marine Technology Center (MTC) to assess its wake wash. The fin was located at three different positions, which are at bow, center and stern of the ship. The results based on wave height measurements at the various fin locations showed that the fin located at the stern position produces lower wake wash compared to other positions.
Small high speed passenger crafts (HSC) are commonly known for their poor seakeeping qualities. T... more Small high speed passenger crafts (HSC) are commonly known for their poor seakeeping qualities. These crafts are frequently exposed to large slamming impacts and these repetitive shocks may pose danger to passengers’ safety and health. In Malaysia, small high speed passenger crafts having lengths between 7 to 9 meters are mainly used to transport tourists between popular island destinations. Evaluation on impact and vibration for this type of craft was conducted by using accelerometers attached to several locations on craft’s deck. The test was conducted at speeds ranged between 20 to 30 knots and the highest peak accelerations were recorded. The highest acceleration record during the sea trial was recorded at 4.22 g and the average acceleration measure is 2.20 g. Apart from this test, evaluation on effectiveness of the current foam seat typically used in this craft were evaluated using Dynamic Response Index (DRI) and results have shown that the seat is less efficient when impact r...
2018 4th International Symposium on Geoinformatics (ISyG), 2018
FES 2014 tidal satellite altimetry data has been used to know the distribution of regions in Indo... more FES 2014 tidal satellite altimetry data has been used to know the distribution of regions in Indonesia that have the potential to develop tidal energy. Based on the value of tidal range obtained in each region, calculation estimates the amount of energy that can be produced. Calculation of tidal energy potential has been done using tidal barrage tool design. Based on this research, Southwest of Papua Island has the highest tidal range in Indonesia of more than 5 meters, while west of Sumatera Island (in the north) and southwest of Kalimantan Island have the lowest tidal range less of than 1 meter. Based on our analysis, Bagan Siapi-api (near Halang Island), Bagan Siapi-api (near Rupat Island), North Tembilahan, South Tembilahan, Gulf of Bintuni, South East of Papua (near Arafura Sea) and South of Papua (near Arafura Sea) are the potential locations for development of tidal energy with tidal barrage device. The prediction of electrical power that can be harnessed ranged from 60.45 MW to 3719.13 MW. The highest power that can be obtained is in the area of Gulf of Bintuni and the lowest power is in the area of Bagan Siapi-api (near Halang Island). Southwest of Papua and Northeast of Sumatera are the most reliable regions to develop tidal energy.
Marine propeller hydrodynamics and noise study is an important problem in the suitable performanc... more Marine propeller hydrodynamics and noise study is an important problem in the suitable performance of ships and submarines. In the first step of this paper, the hydrodynamics of two propellers was studied under different operating conditions.Thensheet cavitation inception and development conditions were obtained in order to understand the impact of varying rotational speed of the propeller and pressure drop on the propeller noise. In the second step overall sound pressure levels (SPLs) under non-cavitating and sheet cavitating conditions were extracted for each of these models. The overall SPLs were calculated from Ffowcs Williams and Hawkings(FW-H) equations and its integral solutions. In this work, the flow field was analysed with the FVM, and then flow data including; pressure fluctuations, sheet cavitation volume and velocity magnitude results of the flow solution were used as the input for the FW-H formulation to predict the overall SPLs. The results from flow analysis are sig...
Abstract Ship generated waves (SGW) can cause bank erosion, disturbance to moored boats and bad i... more Abstract Ship generated waves (SGW) can cause bank erosion, disturbance to moored boats and bad impact on the environment especially in confined water. One of the important vessel parameters that will affect the SGW is the speed of the boat. The speed limit determination for fishing boats in confined water will be discussed which can be used as a reference to decide the maximum boat or ship speed. The confined water of Mersing River has been chosen for the current study. This river is a busy river located in Johor in the southeast area of Peninsular Malaysia. The limited speed is needed in this river because the river is restricted to many boat activities. The typical boat particulars in Mersing River are 14.05 m in length, 4.35 m in breadth and 1 m in draft. The field experiment has been conducted with several scenarios considering the speed and tidal conditions. The results of the experiment were used to determine the maximum energy of SGW in this area. By using trendline characteristics, the formula of maximum energy was generated by considering the speed of the boat. The Brisbane River Criteria in Australian River has been selected due to the same characteristic with Mersing River. Hence, the reference for allowable energy was defined in this study. By using this river criteria, the limit of the boat speed was provided for all tidal conditions (ebbing, slack and flooding), and it was found that the allowable speed as the speed limit in the Mersing River is 5 knots. This will reduce bank erosion, disturbance to moored boats, environmental impacts and energy consumption. Moreover, the generating process of the formula can be a reference to get the speed limit at particular area as the river in other areas.
The development of microchannels with open flow for use in irrigation and rainy areas is challeng... more The development of microchannels with open flow for use in irrigation and rainy areas is challenged by electricity generation via hydrokinetic devices in shallow and low velocity flows. Conventional hydrokinetic turbines are known to be highly dependent on current speed and water depth. Another drawback of conventional turbines is their low efficiency. These shortcomings lead to the need to accelerate the flow in the channel system to enhance the extracted power. The method of deploying a novel turbine configuration in irrigation channels can help overcome the low performance of conventional hydrokinetic turbines. Therefore, this study experimentally presents a bidirectional diffuser-augmented channel that includes dual cross flow/Banki turbines. Results show that the maximum efficiency of the overall system with two turbines is nearly 55.7%. The efficiency is low relative to that of hydraulic turbines. Nevertheless, the result can be considered satisfactory given the low head of the present system. The use of this system will contribute to a highly efficient utilization of flows in rivers and channels for electrical energy generation in rural areas.
International Journal of Applied Mechanics and Engineering, 2019
Evaluation of impact loads when a ship hull contacts the wave surface is one of the main issues f... more Evaluation of impact loads when a ship hull contacts the wave surface is one of the main issues for researchers who are going to design the structure of marine vehicles. In this paper, the results of experimental tests and numerical modeling of the distribution of pressure on different wedge-shaped models are reported and the effect of related parameters such as the deadrise angles, the weight and drop heights, is assessed. The output of analyses and the results can give appropriate approximations of the maximum impact pressures for the geometries that are similar to marine vehicle’s hull sections to estimate the hydrodynamic impact loads in different sea-states. In addition, other effective parameters such as the impact speed, acceleration and water entry process can be used for evaluating the performance of such crafts.
Development and application of offshore wind turbine farms have been increasing, particularly in ... more Development and application of offshore wind turbine farms have been increasing, particularly in the developed countries, because of their high power rating, high yield energy, high offshore wind, and unlimited space in the offshore. However, the poor data and simplistic methodologies of the previous assessments result in insufficient estimates of the wind energy potential. Thus, this study provides an assessment of the offshore wind energy resources in Malaysia using multi-mission satellite altimetry data. The satellite altimetry data was extracted from Radar Altimeter Database Systems located at GNSS and Geodynamics Laboratory, Universiti Teknologi Malaysia. The data were validated by buoy measurements from two offshore sites, as indicated by the high correlation coefficient of 0.88. Further, the offshore wind energy resource mapping data in Malaysia identified three areas in Peninsular Malaysia and Borneo as potential areas for offshore wind energy development.
According to the Third Greenhouse Gas (GHG) Study 2014 of International Maritime Organization (IM... more According to the Third Greenhouse Gas (GHG) Study 2014 of International Maritime Organization (IMO), the total emission in 2012 are estimated to be 949 million tonnes which is 2.7% of global CO 2 emission by total shipping and expected to increase from 2012 levels by 50-250% by 2050. Significant changes are needed to all industry by implementation of energy efficiency design and operational measures to meet existing and future global emission reduction targets. Although the fuel cost-reducing effects of some energy efficiency measures and new technologies are well established and matured, shipping companies appear reluctant to adopt them. Besides, it is observed that the stakeholders are directly or indirectly involved for implementation of energy efficiency measures in shipping industry. Therefore, the objective for this study was to identify the barriers to energy efficiency operational measures by a qualitative survey among various stakeholders from all corners of shipping industry. It has been found in the research that the barriers for implementation of all cost-free operational measures are almost the same such as lack of information of the measure, lack of awareness and competence of ship crews and operation difficulties which are in nature of information and technical barriers. But financial issue and owner's interest are the key barriers for some other operational measures which are related to costing and need investment for implementation.
Renewable & Sustainable Energy Reviews, Sep 1, 2017
One of the most abundant energy sources exists in this world is the ocean wave energy. By far, it... more One of the most abundant energy sources exists in this world is the ocean wave energy. By far, it has shown to be the most clean, renewable, predicted energy and has raised the potential to compete with the current use of nonrenewable energy sources. Recent research conducted on wave energy invention has opened a new dimension to slowly reduce the dependency on fossil fuel by introducing new technology on the renewable world but relatively lacking in economical aspect. This review brings the latest status on integration of wave energy device with other marine facilities, which is the breakwater structure that may possibly aid to cost sharing. Most researches done on this field highlighted countries experiencing rough sea condition and focused less on countries with medium wave condition as faced by the Asian continent. The potential for energy extraction and wave dissipation for medium wave condition will be discussed in this review by considering several aspects including reliability, effectiveness and performance. Finally, this review shows that the integration opens up a new dimension to acknowledge the technology harnessing ocean wave, especially for the Asian countries experiencing medium wave condition.
This paper describes the implementation of a PIC microcontroller in a conventional laboratory-typ... more This paper describes the implementation of a PIC microcontroller in a conventional laboratory-type electronic trainer. The work comprises software for the PIC and hardware for the software. The PIC controller uses an EasyPIC-6 board and includes a PC-interfaced programmer for the PIC chip. It has many external modules: 128 × 64 graphic LCD display, 2 × 16 LCD display, 4 × 4 keypad, and port expander, all in the same bench. The trainer is capable of 36 experiments in logic/analogue electronic and control systems. A 5-sided approximate sensor, two photoelectric sensors (BR56-DDT-P and BEN9M-TFR), four CMOS, four BCD-7-segment driven by CD4511B, two relays (2-pole and 3-pole), six voltages, ammeter measurement, DC motor, and 24VDC power supply, connect through connectors and pinions. Results of all the experiments show the trainer satisfying requirements of undergraduate and postgraduate projects involving conventional electronic and classical control systems.
The present article illustrates the modeling and optimization of a dual-slot waveguide for the ap... more The present article illustrates the modeling and optimization of a dual-slot waveguide for the application of a refractive index biosensor. The nanometer scale waveguide structure uses the silicon-on-insulator platform for the consideration of higher sensitivity and compactness of a resonator biosensor. The modal analysis is performed using the finite difference method based on full vector eigenmode calculation. The maximum field penetration in the lower index region is found for the quasi-TE mode. The sensitivity is maximized through the optimization of the waveguide dimension by relating effective refractive index with the dispersion of a waveguide. The biosensor showed the maximum calculated sensitivity of 461.327 nm/RIU and a limit-of-detection of 2.601 × 10-6 RIU (where RIU denotes refractive index unit).
International journal of innovative technology and exploring engineering, Oct 30, 2019
Multistage-overtopping wave energy device is an example of the overtopping concept in extracting ... more Multistage-overtopping wave energy device is an example of the overtopping concept in extracting energy from the ocean wave. The multistage opening allows the wave to overtop and stored inside the multistage reservoirs and later used for electricity generation. Previously, using concentrated V-shape-ramp on the conventional multi-reservoir Sea Slot-Cone Generator (SSG) has been proven to improve up to 67 percent in hydraulic power at the 3.5 meters of significant wave height and 9.3 meters of wave period. However, the performance begins to drop when operating at smaller wave height consisting of 2.5-meter significant wave height and 7.9 seconds of wave period. Thus, this follow-up paper presents a numerical study to improve device performance, especially at small wave height. Five breakwater-ramp designs were tested consisting of Basis, Design 1 to Design 5. The overtopping device performance was simulated using FLOW-3D CFD software. Results are presented in the form of mean overtopping discharge or potential energy stored and the total energy potential for each propose breakwater-ramp design. The numerical results show that the highest total energy potential represents as the potential power output is recorded by Design 4 and Design 5 with 63.26 and 63.05 kW respectively, compared to basis SSG device with only 29.14 kW at the wave height of 2.8 meters and a wave period of 9.3 seconds.
The aim of our paper is to study the effects of roll motion on a transverse stability of a small ... more The aim of our paper is to study the effects of roll motion on a transverse stability of a small boat. Roll frequency will be calculated and analyzed for reducing motion sickness based on stabilit solution of ship roll motion will be also investigated in our paper.
This study suggests a new approach for the reduction of fuel consumption and CO2 emission with th... more This study suggests a new approach for the reduction of fuel consumption and CO2 emission with the assist of renewable energy. The focus of the study is the adaptation of wind power electrical generating system onboard. The electricity generated from wind is believed able to help reduce the fuel oil consumption and CO2 emission. A product oil tanker has been selected for the case study. The route of study is the round trip from Singapore to Jeddah and Taichung to Singapore. Wind power generation is calculated based on available of wind data along the routes. Economic assessment has been carried out to assess the feasibility of investment in this project. With the use of simple payback method, the result shows that investment cost will be repaid within 10 years. Besides, Net Present Value indicates a positive value within an investment period of 16 years by 10% internal rate of return. The installation of the system onboard gives a significant reduction in fuel oil consumption and CO2 emission. A 38.69% of saving can be achieved in a year for vessels which travel through the selected routes of study in normal sea going condition. Keywords : Wind turbine; green energy; FO and CO2 emission reduction
Wake wash has become a significant issue in the ship design industry due to its impact on the env... more Wake wash has become a significant issue in the ship design industry due to its impact on the environment in terms of erosion of natural shoreline wetlands. Many ideas for reducing wake wash have been introduced. This research work presents the development of a low wake wash catamaran hull form. In particular, the study is focused on the effectiveness of specially designed fin in order to reduce the wake wash produced by the ship. The fin was attached vertically along the centerline of the catamaran model and the model was tested in the towing tank of Marine Technology Center (MTC) to assess its wake wash. The fin was located at three different positions, which are at bow, center and stern of the ship. The results based on wave height measurements at the various fin locations showed that the fin located at the stern position produces lower wake wash compared to other positions.
Small high speed passenger crafts (HSC) are commonly known for their poor seakeeping qualities. T... more Small high speed passenger crafts (HSC) are commonly known for their poor seakeeping qualities. These crafts are frequently exposed to large slamming impacts and these repetitive shocks may pose danger to passengers’ safety and health. In Malaysia, small high speed passenger crafts having lengths between 7 to 9 meters are mainly used to transport tourists between popular island destinations. Evaluation on impact and vibration for this type of craft was conducted by using accelerometers attached to several locations on craft’s deck. The test was conducted at speeds ranged between 20 to 30 knots and the highest peak accelerations were recorded. The highest acceleration record during the sea trial was recorded at 4.22 g and the average acceleration measure is 2.20 g. Apart from this test, evaluation on effectiveness of the current foam seat typically used in this craft were evaluated using Dynamic Response Index (DRI) and results have shown that the seat is less efficient when impact r...
2018 4th International Symposium on Geoinformatics (ISyG), 2018
FES 2014 tidal satellite altimetry data has been used to know the distribution of regions in Indo... more FES 2014 tidal satellite altimetry data has been used to know the distribution of regions in Indonesia that have the potential to develop tidal energy. Based on the value of tidal range obtained in each region, calculation estimates the amount of energy that can be produced. Calculation of tidal energy potential has been done using tidal barrage tool design. Based on this research, Southwest of Papua Island has the highest tidal range in Indonesia of more than 5 meters, while west of Sumatera Island (in the north) and southwest of Kalimantan Island have the lowest tidal range less of than 1 meter. Based on our analysis, Bagan Siapi-api (near Halang Island), Bagan Siapi-api (near Rupat Island), North Tembilahan, South Tembilahan, Gulf of Bintuni, South East of Papua (near Arafura Sea) and South of Papua (near Arafura Sea) are the potential locations for development of tidal energy with tidal barrage device. The prediction of electrical power that can be harnessed ranged from 60.45 MW to 3719.13 MW. The highest power that can be obtained is in the area of Gulf of Bintuni and the lowest power is in the area of Bagan Siapi-api (near Halang Island). Southwest of Papua and Northeast of Sumatera are the most reliable regions to develop tidal energy.
Marine propeller hydrodynamics and noise study is an important problem in the suitable performanc... more Marine propeller hydrodynamics and noise study is an important problem in the suitable performance of ships and submarines. In the first step of this paper, the hydrodynamics of two propellers was studied under different operating conditions.Thensheet cavitation inception and development conditions were obtained in order to understand the impact of varying rotational speed of the propeller and pressure drop on the propeller noise. In the second step overall sound pressure levels (SPLs) under non-cavitating and sheet cavitating conditions were extracted for each of these models. The overall SPLs were calculated from Ffowcs Williams and Hawkings(FW-H) equations and its integral solutions. In this work, the flow field was analysed with the FVM, and then flow data including; pressure fluctuations, sheet cavitation volume and velocity magnitude results of the flow solution were used as the input for the FW-H formulation to predict the overall SPLs. The results from flow analysis are sig...
Abstract Ship generated waves (SGW) can cause bank erosion, disturbance to moored boats and bad i... more Abstract Ship generated waves (SGW) can cause bank erosion, disturbance to moored boats and bad impact on the environment especially in confined water. One of the important vessel parameters that will affect the SGW is the speed of the boat. The speed limit determination for fishing boats in confined water will be discussed which can be used as a reference to decide the maximum boat or ship speed. The confined water of Mersing River has been chosen for the current study. This river is a busy river located in Johor in the southeast area of Peninsular Malaysia. The limited speed is needed in this river because the river is restricted to many boat activities. The typical boat particulars in Mersing River are 14.05 m in length, 4.35 m in breadth and 1 m in draft. The field experiment has been conducted with several scenarios considering the speed and tidal conditions. The results of the experiment were used to determine the maximum energy of SGW in this area. By using trendline characteristics, the formula of maximum energy was generated by considering the speed of the boat. The Brisbane River Criteria in Australian River has been selected due to the same characteristic with Mersing River. Hence, the reference for allowable energy was defined in this study. By using this river criteria, the limit of the boat speed was provided for all tidal conditions (ebbing, slack and flooding), and it was found that the allowable speed as the speed limit in the Mersing River is 5 knots. This will reduce bank erosion, disturbance to moored boats, environmental impacts and energy consumption. Moreover, the generating process of the formula can be a reference to get the speed limit at particular area as the river in other areas.
The development of microchannels with open flow for use in irrigation and rainy areas is challeng... more The development of microchannels with open flow for use in irrigation and rainy areas is challenged by electricity generation via hydrokinetic devices in shallow and low velocity flows. Conventional hydrokinetic turbines are known to be highly dependent on current speed and water depth. Another drawback of conventional turbines is their low efficiency. These shortcomings lead to the need to accelerate the flow in the channel system to enhance the extracted power. The method of deploying a novel turbine configuration in irrigation channels can help overcome the low performance of conventional hydrokinetic turbines. Therefore, this study experimentally presents a bidirectional diffuser-augmented channel that includes dual cross flow/Banki turbines. Results show that the maximum efficiency of the overall system with two turbines is nearly 55.7%. The efficiency is low relative to that of hydraulic turbines. Nevertheless, the result can be considered satisfactory given the low head of the present system. The use of this system will contribute to a highly efficient utilization of flows in rivers and channels for electrical energy generation in rural areas.
International Journal of Applied Mechanics and Engineering, 2019
Evaluation of impact loads when a ship hull contacts the wave surface is one of the main issues f... more Evaluation of impact loads when a ship hull contacts the wave surface is one of the main issues for researchers who are going to design the structure of marine vehicles. In this paper, the results of experimental tests and numerical modeling of the distribution of pressure on different wedge-shaped models are reported and the effect of related parameters such as the deadrise angles, the weight and drop heights, is assessed. The output of analyses and the results can give appropriate approximations of the maximum impact pressures for the geometries that are similar to marine vehicle’s hull sections to estimate the hydrodynamic impact loads in different sea-states. In addition, other effective parameters such as the impact speed, acceleration and water entry process can be used for evaluating the performance of such crafts.
Development and application of offshore wind turbine farms have been increasing, particularly in ... more Development and application of offshore wind turbine farms have been increasing, particularly in the developed countries, because of their high power rating, high yield energy, high offshore wind, and unlimited space in the offshore. However, the poor data and simplistic methodologies of the previous assessments result in insufficient estimates of the wind energy potential. Thus, this study provides an assessment of the offshore wind energy resources in Malaysia using multi-mission satellite altimetry data. The satellite altimetry data was extracted from Radar Altimeter Database Systems located at GNSS and Geodynamics Laboratory, Universiti Teknologi Malaysia. The data were validated by buoy measurements from two offshore sites, as indicated by the high correlation coefficient of 0.88. Further, the offshore wind energy resource mapping data in Malaysia identified three areas in Peninsular Malaysia and Borneo as potential areas for offshore wind energy development.
According to the Third Greenhouse Gas (GHG) Study 2014 of International Maritime Organization (IM... more According to the Third Greenhouse Gas (GHG) Study 2014 of International Maritime Organization (IMO), the total emission in 2012 are estimated to be 949 million tonnes which is 2.7% of global CO 2 emission by total shipping and expected to increase from 2012 levels by 50-250% by 2050. Significant changes are needed to all industry by implementation of energy efficiency design and operational measures to meet existing and future global emission reduction targets. Although the fuel cost-reducing effects of some energy efficiency measures and new technologies are well established and matured, shipping companies appear reluctant to adopt them. Besides, it is observed that the stakeholders are directly or indirectly involved for implementation of energy efficiency measures in shipping industry. Therefore, the objective for this study was to identify the barriers to energy efficiency operational measures by a qualitative survey among various stakeholders from all corners of shipping industry. It has been found in the research that the barriers for implementation of all cost-free operational measures are almost the same such as lack of information of the measure, lack of awareness and competence of ship crews and operation difficulties which are in nature of information and technical barriers. But financial issue and owner's interest are the key barriers for some other operational measures which are related to costing and need investment for implementation.
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