nasir mehmood - Academia.edu (original) (raw)

Papers by nasir mehmood

The world is heavily dependent on fossil fuels since most of its energy requirements are fulfille... more The world is heavily dependent on fossil fuels since most of its energy requirements are fulfilled by conventional methods of burning these fuels. The energy demand is increasing by day with growing population. The energy production by fossil fuels is devastating the environment and survival of life on globe is endangered. The renewal energy technologies are vital to ensure future energy sustenance and environmental issues. Ocean is a vast resource of renewable energy. The technology today makes it possible to extract energy from tides. The growing interest in exploring tidal current technologies has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The purpose of this study is to present a comprehensive review of tidal current technologies to harness ocean energy. The ocean energy resources are presented. The author discusses tidal energy technologies. The tidal current turbines are discussed in detail. The author reviews today's popular tidal current technologies. The present status of ocean energy development is also reported.

The renewal energy technologies are increasingly popular to ensure future energy sustenance and a... more The renewal energy technologies are increasingly popular to ensure future energy sustenance and address environmental issues. The tides are enormous and consistent untapped resource of renewable energy. The growing interest in exploring tidal energy has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The tidal energy industry is undergoing an increasing shift towards diffuser augmented turbines. The reason is the higher power output of diffuser augmented turbines compared to conventional open turbines. The purpose of this study is to present a comprehensive review of diffuser augmented horizontal axis tidal current turbines. The components, relative advantages, limitations and design parameters of diffuser augmented horizontal axis tidal current turbines are presented in detail. CFD simulation of NACA 0016 airfoil is carried out to explore its potential for designing a diffuser. The core issues associated with diffuser augmented horizontal axis tidal current turbines are also discussed.

ABSTRACT Today, the world is heavily dependent on fossil fuels, as most of the energy requirement... more ABSTRACT Today, the world is heavily dependent on fossil fuels, as most of the energy requirements are being met through conventional methods of burning these fuels. The energy demand is increasing day with growing population. Consequently, fossil fuel reserves are depleting continuously and will soon run out in coming years. Therefore, renewable energy resources have gained enormous attention in recent years. The growing interest in exploring tidal current technologies has many compelling reasons such as its renewable nature, tidal energy is cleaner than fossil fuels, intermittent but predictable, security and diversity of supply, and limited social and environmental impacts. Tidal current technologies are still in development phase, yet need some time to mature to prove their full potential. Tidal current turbine is an important tidal current technology. The purpose of this paper is to present a comprehensive review of tidal current turbine, its potential and associated challenges. The paper discusses general theoretical background of fluid flow in a tidal stream and forces governing the flow behavior. The author will also discuss the core issues and challenges faced in research and development such as unforgiving marine environment, corrosion, cavitation phenomena and extreme structural loads.

Lecture Notes in Electrical Engineering, 2012

Digital video watermarking has been proposed as a scheme for copyright protection and content aut... more Digital video watermarking has been proposed as a scheme for copyright protection and content authentication for digital video data. H. 264/AVC is a video compression standard that outperforms previous video coding standards due to its coding efficiency. In this article, we propose a blind watermarking algorithm for H. 264/AVC video stream that is based on intra 4x4 prediction modes. Our proposed scheme is blind and original un-watermarked stream is not required to extract the watermark. Watermark extraction process is simple ...

37th Annual IEEE Conference on Local Computer Networks -- Workshops, 2012

Digital watermarking has been proposed as an effective scheme for copyright protection and conten... more Digital watermarking has been proposed as an effective scheme for copyright protection and content authentication. Fragile video watermarking is a type of video watermarking in which embedded watermark in the digital signal is destroyed when the signal is tempered or manipulated illegally. Authenticity of video streams can be proven by embedding fragile watermarks. We propose a fragile watermarking scheme for H.264/AVC video authentication. The scheme embeds fragile watermark in intra 4x4 (I4x4) prediction modes in the intra (I) frames only during encoding. The watermark is generated from features that are robust to recompression and is embedded into the prediction modes according to defined mapping rules. Experimental results show that our proposed scheme is sensitive to recompression and has a very low effect on the video quality and bitrate. Watermark can be embedded during encoding stage and authentication is verified during decoding process.

Sensing and Bio-Sensing Research, 2014

ABSTRACT With the growing financial burden of chronic wound management in clinics and hospitals, ... more ABSTRACT With the growing financial burden of chronic wound management in clinics and hospitals, it is high time to devise wireless wound monitoring devices to be placed within wound dressing for continuously sensing the wound milieu. Sensors are a vital part of such monitoring system enabling it to sense and measure variations in wound parameters. This paper describes the calibration, characterization and real-time testing of selected temperature, moisture, and pressure sensors deemed suitable for wound monitoring applications. The sensors were chosen on the basis of small size, non-invasiveness, reliable performance, low power consumption and their suitability for placement within wound dressings. All selected sensors were first individually calibrated and characterized using commercially-available software and measurement tools, they are then collectively interfaced to a custom-designed flexible radio-frequency transmitter device for real-time performance measurement within a clinical-grade wound bandage. Experimental results on a mannequin leg have validated the low-power operation, and reliable sensing and data transmission capabilities. The nominal measurement resolutions obtained for temperature, moisture, and pressure were 0.15 °C, 0.85-5%RH, and 0.05-0.56 mmHg respectively

Sensors, 2014

This paper presents the development of an improved mobile-based telemetric dual mode sensing syst... more This paper presents the development of an improved mobile-based telemetric dual mode sensing system to monitor pressure and moisture levels in compression bandages and dressings used for chronic wound management. The system is fabricated on a 0.2 mm thick flexible printed circuit material, and is capable of sensing pressure and moisture at two locations simultaneously within a compression bandage and wound dressing. The sensors are calibrated to sense both parameters accurately, and the data are then transmitted wirelessly to a receiver connected to a mobile device. An error-correction algorithm is developed to compensate the degradation in measurement quality due to battery power drop over time. An Android application is also implemented to automatically receive, process, and display the sensed wound parameters. The performance of the sensing system is first validated on a mannequin limb using a compression bandage and wound dressings, and then tested on a healthy volunteer to acquire real-time performance parameters. The results obtained here suggest that this dual mode sensor can perform reliably when placed on a human limb.

Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2014

The management of chronic wounds has emerged as a major health care challenge during the 21st cen... more The management of chronic wounds has emerged as a major health care challenge during the 21st century consuming, significant portions of health care budgets. Chronic wounds such as diabetic foot ulcers, leg ulcers, and pressure sores have a significant negative impact on the quality of life of affected individuals. Covering wounds with suitable dressings facilitates the healing process and is common practice in wound management plans. However, standard dressings do not provide insights into the status of the wound underneath. Parameters such as moisture, pressure, temperature and pH inside the dressings are indicative of the healing rate, infection, and wound healing phase. But owing to the lack of information available from within the dressings, these are often changed to inspect the wound, disturbing the normal healing process of wounds in addition to causing pain to the patient. Sensors embedded in the dressing would provide clinicians and nurses with important information that would aid in wound care decision making, improve patient comfort, and reduce the frequency of dressing changes. The potential benefits of this enabling technology would be seen in terms of a reduction in hospitalization time and health care cost. Modern sensing technology along with wireless radio frequency communication technology is poised to make significant advances in wound management. This review discusses issues related to the design and implementation of sensor technology and telemetry systems both incorporated in wound dressings to devise an automated wound monitoring technology, and also surveys the literature available on current sensor and wireless telemetry systems.

The world is heavily dependent on fossil fuels since most of its energy requirements are fulfille... more The world is heavily dependent on fossil fuels since most of its energy requirements are fulfilled by conventional methods of burning these fuels. The energy demand is increasing by day with growing population. The energy production by fossil fuels is devastating the environment and survival of life on globe is endangered. The renewal energy technologies are vital to ensure future energy sustenance and environmental issues. Ocean is a vast resource of renewable energy. The technology today makes it possible to extract energy from tides. The growing interest in exploring tidal current technologies has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The purpose of this study is to present a comprehensive review of tidal current technologies to harness ocean energy. The ocean energy resources are presented. The author discusses tidal energy technologies. The tidal current turbines are discussed in detail. The author reviews today's popular tidal current technologies. The present status of ocean energy development is also reported.

The renewal energy technologies are increasingly popular to ensure future energy sustenance and a... more The renewal energy technologies are increasingly popular to ensure future energy sustenance and address environmental issues. The tides are enormous and consistent untapped resource of renewable energy. The growing interest in exploring tidal energy has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The tidal energy industry is undergoing an increasing shift towards diffuser augmented turbines. The reason is the higher power output of diffuser augmented turbines compared to conventional open turbines. The purpose of this study is to present a comprehensive review of diffuser augmented horizontal axis tidal current turbines. The components, relative advantages, limitations and design parameters of diffuser augmented horizontal axis tidal current turbines are presented in detail. CFD simulation of NACA 0016 airfoil is carried out to explore its potential for designing a diffuser. The core issues associated with diffuser augmented horizontal axis tidal current turbines are also discussed.

ABSTRACT Today, the world is heavily dependent on fossil fuels, as most of the energy requirement... more ABSTRACT Today, the world is heavily dependent on fossil fuels, as most of the energy requirements are being met through conventional methods of burning these fuels. The energy demand is increasing day with growing population. Consequently, fossil fuel reserves are depleting continuously and will soon run out in coming years. Therefore, renewable energy resources have gained enormous attention in recent years. The growing interest in exploring tidal current technologies has many compelling reasons such as its renewable nature, tidal energy is cleaner than fossil fuels, intermittent but predictable, security and diversity of supply, and limited social and environmental impacts. Tidal current technologies are still in development phase, yet need some time to mature to prove their full potential. Tidal current turbine is an important tidal current technology. The purpose of this paper is to present a comprehensive review of tidal current turbine, its potential and associated challenges. The paper discusses general theoretical background of fluid flow in a tidal stream and forces governing the flow behavior. The author will also discuss the core issues and challenges faced in research and development such as unforgiving marine environment, corrosion, cavitation phenomena and extreme structural loads.

Lecture Notes in Electrical Engineering, 2012

Digital video watermarking has been proposed as a scheme for copyright protection and content aut... more Digital video watermarking has been proposed as a scheme for copyright protection and content authentication for digital video data. H. 264/AVC is a video compression standard that outperforms previous video coding standards due to its coding efficiency. In this article, we propose a blind watermarking algorithm for H. 264/AVC video stream that is based on intra 4x4 prediction modes. Our proposed scheme is blind and original un-watermarked stream is not required to extract the watermark. Watermark extraction process is simple ...

37th Annual IEEE Conference on Local Computer Networks -- Workshops, 2012

Digital watermarking has been proposed as an effective scheme for copyright protection and conten... more Digital watermarking has been proposed as an effective scheme for copyright protection and content authentication. Fragile video watermarking is a type of video watermarking in which embedded watermark in the digital signal is destroyed when the signal is tempered or manipulated illegally. Authenticity of video streams can be proven by embedding fragile watermarks. We propose a fragile watermarking scheme for H.264/AVC video authentication. The scheme embeds fragile watermark in intra 4x4 (I4x4) prediction modes in the intra (I) frames only during encoding. The watermark is generated from features that are robust to recompression and is embedded into the prediction modes according to defined mapping rules. Experimental results show that our proposed scheme is sensitive to recompression and has a very low effect on the video quality and bitrate. Watermark can be embedded during encoding stage and authentication is verified during decoding process.

Sensing and Bio-Sensing Research, 2014

ABSTRACT With the growing financial burden of chronic wound management in clinics and hospitals, ... more ABSTRACT With the growing financial burden of chronic wound management in clinics and hospitals, it is high time to devise wireless wound monitoring devices to be placed within wound dressing for continuously sensing the wound milieu. Sensors are a vital part of such monitoring system enabling it to sense and measure variations in wound parameters. This paper describes the calibration, characterization and real-time testing of selected temperature, moisture, and pressure sensors deemed suitable for wound monitoring applications. The sensors were chosen on the basis of small size, non-invasiveness, reliable performance, low power consumption and their suitability for placement within wound dressings. All selected sensors were first individually calibrated and characterized using commercially-available software and measurement tools, they are then collectively interfaced to a custom-designed flexible radio-frequency transmitter device for real-time performance measurement within a clinical-grade wound bandage. Experimental results on a mannequin leg have validated the low-power operation, and reliable sensing and data transmission capabilities. The nominal measurement resolutions obtained for temperature, moisture, and pressure were 0.15 °C, 0.85-5%RH, and 0.05-0.56 mmHg respectively

Sensors, 2014

This paper presents the development of an improved mobile-based telemetric dual mode sensing syst... more This paper presents the development of an improved mobile-based telemetric dual mode sensing system to monitor pressure and moisture levels in compression bandages and dressings used for chronic wound management. The system is fabricated on a 0.2 mm thick flexible printed circuit material, and is capable of sensing pressure and moisture at two locations simultaneously within a compression bandage and wound dressing. The sensors are calibrated to sense both parameters accurately, and the data are then transmitted wirelessly to a receiver connected to a mobile device. An error-correction algorithm is developed to compensate the degradation in measurement quality due to battery power drop over time. An Android application is also implemented to automatically receive, process, and display the sensed wound parameters. The performance of the sensing system is first validated on a mannequin limb using a compression bandage and wound dressings, and then tested on a healthy volunteer to acquire real-time performance parameters. The results obtained here suggest that this dual mode sensor can perform reliably when placed on a human limb.

Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2014

The management of chronic wounds has emerged as a major health care challenge during the 21st cen... more The management of chronic wounds has emerged as a major health care challenge during the 21st century consuming, significant portions of health care budgets. Chronic wounds such as diabetic foot ulcers, leg ulcers, and pressure sores have a significant negative impact on the quality of life of affected individuals. Covering wounds with suitable dressings facilitates the healing process and is common practice in wound management plans. However, standard dressings do not provide insights into the status of the wound underneath. Parameters such as moisture, pressure, temperature and pH inside the dressings are indicative of the healing rate, infection, and wound healing phase. But owing to the lack of information available from within the dressings, these are often changed to inspect the wound, disturbing the normal healing process of wounds in addition to causing pain to the patient. Sensors embedded in the dressing would provide clinicians and nurses with important information that would aid in wound care decision making, improve patient comfort, and reduce the frequency of dressing changes. The potential benefits of this enabling technology would be seen in terms of a reduction in hospitalization time and health care cost. Modern sensing technology along with wireless radio frequency communication technology is poised to make significant advances in wound management. This review discusses issues related to the design and implementation of sensor technology and telemetry systems both incorporated in wound dressings to devise an automated wound monitoring technology, and also surveys the literature available on current sensor and wireless telemetry systems.