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Economic outcomes and expectations may differ between developing and developed countries, primarily due to different stages of economic development. Nonetheless, governments of developing and developed countries alike are focusing on sustainable economic development (SED) to ensure self-sufficiency in food, total employment, and financial stability without relying on foreign aid. To achieve these objectives, governments continue to exploit natural resources via unsustainable industrialisation, causing deforestation and air and water pollution, which ultimately destroys the natural ecosystem. Unfortunately, the general perception is that environmental conservation will not bring any commercial benefits. Instead, conservation relies on the government’s or institution’s budget to maintain the order of ecology and in return minimise environmental impacts. Though some empirical studies argue that corporate environmental efforts bring in good revenue through tourism spending, environmentally friendly industries, green-label industries, and environment-conscious investments, both developing and developed countries continue to emphasise economic development rather than environmental performance. Therefore, this study aimed to investigate the relationship of sustainable economic development (SED) and environmental performance (EP) via moderating effect of country governance (CG) in developing and developed countries. The underpinning theories adopted in this study were the Environmental Kuznets Curve (EKC), Ecological Modernisation Theory (EMT), Neoliberal Environmental Governance (NEG), and Great Moderation (GM). Past studies on the nexus between SED, EP, and CG have focused on the company or institution level. This study, in contrast, addressed the country level in terms of developing and developed countries. Data on SED was obtained from the World Bank and International Monetary Fund (IMF) database, which included Gross Domestic Product (GDP), Foreign Direct Investment (F

At present, many economies are suffering from environmental problems that have significant effects on the climate and life of human beings, thus, the governments and institutions work to reduce the industrial negative effects on the environment. Past studies focus on the nexus of sustainable economic development (SED) and environmental performance (EP) at the company or institution level. This study focused on the country level, and also further examined the outcome in developing and developed countries. This study examines the nexus between sustainable economic development and environmental performance of both developed and developing countries. The data of SED obtained from World Bank and Environmental Performance Index (EPI) for the period 2006-2016. This study also takes into consideration the control variable (CV) of primary school enrolment (SCH) and country population (POP), which may potentially influence the outcome of this study. For the analysis, the study employs panel regression model. The findings revealed that most of the proxies of SED have significant relationship with EPI.

At present, many economies are suffering from environmental problems that have significant effects on the climate and life of human beings, thus, the governments and institutions work to reduce the industrial negative effects on the environment. Past studies focus on the nexus of sustainable economic development (SED) and environmental performance (EP) at the company or institution level. This study focused on the country level, and also further examined the outcome in developing and developed countries. This study examines the nexus between sustainable economic development and environmental performance of both developed and developing countries. The data of SED obtained from World Bank and Environmental Performance Index (EPI) for the period 2006-2016. This study also takes into consideration the control variable (CV) of primary school enrolment (SCH) and country population (POP), which may potentially influence the outcome of this study. For the analysis, the study employs panel regression model. The findings revealed that most of the proxies of SED have significant relationship with EPI.

We present finite difference time domain simulation to analyze the optical absorption enhancement of metal-semiconductor-metal photo detectors employing double plasmonic grating structures. Simulation results show that the combination of a subwavelength aperture and double nano-structured metal grating results in up to 25 times enhancement in optical absorption, in comparison to MSM photodetector structures employing only a subwavelength aperture. This improvement of the absorption enhancement is due to the coupling out function of the bottom grating structure which distributes the light to both side of the subwavelength aperture.

We present finite difference time domain simulation to analyze the optical absorption enhancement of metal-semiconductor-metal photo detectors employing double plasmonic grating structures. Simulation results show that the combination of a subwavelength aperture and double nano-structured metal grating results in up to 25 times enhancement in optical absorption, in comparison to MSM photodetector structures employing only a subwavelength aperture. This improvement of the absorption enhancement is due to the coupling out function of the bottom grating structure which distributes the light to both side of the subwavelength aperture.

To improve the responsivity of the metal semiconductor metal photodetector (MSM-PD), we propose and demonstrate the use of sub-wavelength slits in conjunction with nano-structured the metal fingers that enhance the light transmission through plasmonic effects. A 4-finger plasmonics-based GaAs MSM-PD structure is optimized geometrically using a 2-D Finite Difference Domain (FDTD) method and developed, leading to more than 7-times enhancement in photocurrent in comparison with the conventional MSM-PD of similar dimensions at a bias voltage as low as 0.3 V. This enhancement is attributed to the coupling of the surface plasmon polaritons (SPPs) with the incident light through the nano-structured metal fingers. This work paves the way for the development of high-responsivity, high-sensitivity, low bias-voltage high-speed MSM-PDs and CMOS-compatible GaAs-based optoelectronic devices.

In this paper, we use the finite difference time-domain (FDTD) method to optimize the TE-polarized light transmission of a metal-semiconductor-metal photodetector (MSM-PD) employing a dielectric waveguide on top of metal nano-gratings. Simulation results demonstrate that the funneling transmission of the TE-polarized light through the nanoslit of the MSM-PD structure is highly dependent on the structure geometries, such as the waveguide and nano-grating heights. We also demonstrate that adding a dielectric waveguide layer on top of the nano-metal gratings supports both the TM- and TE polarizations, and enhances the light transmission for TE-polarization around 3-times in comparison with conventional plasmonics MSMPD structures.

We propose and numerically demonstrate a high absorption hybrid-plasmonic-based metal semiconductor metal photodetector (MSM-PD) comprising metal nanogratings, a subwavelength slit and amorphous silicon or germanium embedded metal nanoparticles (NPs). Simulation results show that by optimizing the metal nanograting parameters, the subwavelength slit and the embedded metal NPs, a 1.3 order of magnitude increase in electric field is attained, leading to 28-fold absorption enhancement, in comparison with conventional MSM-PD structures. This is 3.5 times better than the absorption of surface plasmon polariton (SPP) based MSM-PD structures employing metal nanogratings and a subwavelength slit. This absorption enhancement is due to the ability of the embedded metal NPs to enhance their optical absorption and scattering properties through light-stimulated resonance aided by the conduction electrons of the NPs.

To improve the responsivity of the metal semiconductor metal photodetector (MSM-PD), we propose and demonstrate the use of sub-wavelength slits in conjunction with nano-structured the metal fingers that enhance the light transmission through plasmonic effects. A 4-finger plasmonics-based GaAs MSM-PD structure is optimized geometrically using a 2-D Finite Difference Domain (FDTD) method and developed, leading to more than 7-times enhancement in photocurrent in comparison with the conventional MSM-PD of similar dimensions at a bias voltage as low as 0.3 V. This enhancement is attributed to the coupling of the surface plasmon polaritons (SPPs) with the incident light through the nano-structured metal fingers. This work paves the way for the development of high-responsivity, high-sensitivity, low bias-voltage high-speed MSM-PDs and CMOS-compatible GaAs-based optoelectronic devices.

In this paper, we use the finite difference time-domain (FDTD) method to optimize the TE-polarized light transmission of a metal-semiconductor-metal photodetector (MSM-PD) employing a dielectric waveguide on top of metal nano-gratings. Simulation results demonstrate that the funneling transmission of the TE-polarized light through the nanoslit of the MSM-PD structure is highly dependent on the structure geometries, such as the waveguide and nano-grating heights. We also demonstrate that adding a dielectric waveguide layer on top of the nano-metal gratings supports both the TM- and TE polarizations, and enhances the light transmission for TE-polarization around 3-times in comparison with conventional plasmonics MSMPD structures.

Includes supplementary material, U.S. Navy and commercial ships have been lucrative targets for terrorist organizations. Realizing that ships are most vulnerable while in-port, adequate measures must be employed by port facilities to ensure vessel security. Commercial and naval ports have been set as a national priority in Homeland Security Presidential Directive 13. A successful terrorist strike against a port could produce long-term economic impact. In an attempt to develop a system of systems to prevent and defeat terrorist attacks against foreign and domestic ports, this study approached the threat from three different aspects: terrestrial, seaborne, and internal. This report uses the Systems Engineering Design Process to define the problem, generate alternatives, model scenarios, and analyze results to produce feasible and cost-effective solutions. No single system can address all issues prevalent in the port security problem. The recommended solutions individually address specific threats, namely vehicle-borne improvised explosive devices, small boat swarm tactics, importation of contraband or weapons of mass destruction, and employee sabotage. Although each solution effectively increased port security, improved port security measures resulted in greater cost. Some solutions yielded only marginal gain in effectiveness with drastic increases in cost., NA

Includes supplementary material, U.S. Navy and commercial ships have been lucrative targets for terrorist organizations. Realizing that ships are most vulnerable while in-port, adequate measures must be employed by port facilities to ensure vessel security. Commercial and naval ports have been set as a national priority in Homeland Security Presidential Directive 13. A successful terrorist strike against a port could produce long-term economic impact. In an attempt to develop a system of systems to prevent and defeat terrorist attacks against foreign and domestic ports, this study approached the threat from three different aspects: terrestrial, seaborne, and internal. This report uses the Systems Engineering Design Process to define the problem, generate alternatives, model scenarios, and analyze results to produce feasible and cost-effective solutions. No single system can address all issues prevalent in the port security problem. The recommended solutions individually address specific threats, namely vehicle-borne improvised explosive devices, small boat swarm tactics, importation of contraband or weapons of mass destruction, and employee sabotage. Although each solution effectively increased port security, improved port security measures resulted in greater cost. Some solutions yielded only marginal gain in effectiveness with drastic increases in cost., NA

In this paper, we use the finite difference time-domain (FDTD) method to optimize the light absorption of an ultrafast nano-grating plasmonic GaAs metal-semiconductor-metal photodetector (MSM-PD) employing double metal nano-gratings. The geometry of the MSM-PD is theoretically investigated, leading to improved light absorption near the design wavelength of GaAs due to plasmon-assisted electric and magnetic field concentration through a subwavelength aperture. Simulation results show up to 8- and 21-times light absorption enhancement for the single and double nano-grating structure, respectively, in comparison to conventional MSM-PDs. Experimentally, more than 4 times enhancement in photocurrent is demonstrated for a single top nano-grating MSM-PD in comparison with conventional MSM-PDs.

The finite difference time-domain (FDTD) method is used to simulate the light absorption enhancement in a plasmonic metal-semiconductor-metal photodetector (MSM-PD) structure employing a metal nanograting with phase shifts. The metal fingers of the MSM-PDs are etched at appropriate depths to maximize light absorption through plasmonic effects into a subwavelength aperture. We also analyse the nano-grating phase shift and groove profiles obtained typically in our experiments using focused ion beam milling and atomic force microscopy and discuss the dependency of light absorption enhancement on the nano-gratings phase shift and groove profiles inscribed into MSM-PDs. Our simulation results show that the nano-grating phase shift blue-shifts the wavelength at which the light absorption enhancement is maximum, and that the combined effects of the nano-grating groove shape and phase shift degrade the light absorption enhancement by up to 50%.

In this paper, finite difference time-domain (FDTD) method is used to simulate the light absorption enhancement in a plasmonic metal-semiconductor-metal photodetector (MSM-PD) structure employing a metal nano-grating with phase-shifts. The metal fingers of the MSM-PDs are etched with appropriate depths to maximize light absorption through plasmonic effects into a subwavelength aperture. Simulation results show that the nano-grating phase-shift red-shifts the wavelength at which the light absorption enhancement maximum, and that the combined effects of the nano-grating groove shape and the nano-grating phase-shift, degrade the light absorption enhancement by up to 50%.

Finite difference time-domain (FDTD) analysis is used to investigate the light absorption enhancement factor dependence on the groove shape of the nano-gratings etched into the surfaces of metal-semiconductor-metal photodetector (MSM-PD) structures. By patterning the MSM-PDs with optimized nano-gratings a significant improvement in light absorption near the design wavelength is achieved through plasmon-assisted electric field concentration effects. Simulation results show about 50 times light absorption enhancement for 850 nm light due to improved optical signal propagation through the nano-gratings.

In this paper, we use the finite difference timedomain (FDTD) method to optimize the light absorption of an ultrafast plasmonic GaAs metal-semiconductor-metal photodetector (MSM-PD) employing metal nano-gratings. The MSM-PD is optimized geometrically, leading to improved light absorption near the designed wavelength of GaAs through plasmon-assisted electric and magnetic field concentration through a subwavelength aperture. Simulation results show up to 10-times light absorption enhancement at 867 nm due to surface plasmon polaritons (SPPs) propagation through the metal nano-grating, in comparison to conventional MSM-PD.

We discuss the light absorption enhancement dependence on the design of nano-gratings inscribed into metal-semiconductor-metal photodetector (MSM-PD) structures. Optimal nano-grating design leads to light absorption improvement through plasmon-assisted effects. Finite difference time-domain simulation results show ~50 times light absorption enhancement at 850 nm due to improved optical signal propagation through the nano-gratings. Also, we show that the light absorption enhancement is strongly dependent on the nano-grating shapes.

Finite difference time-domain (FDTD) analysis is used to investigate the light absorption enhancement factor dependence on the groove shape of the nano-gratings etched into the surfaces of metal-semiconductor-metal photodetector (MSM-PD) structures. By patterning the MSM-PDs with optimized nano-gratings a significant improvement in light absorption near the design wavelength is achieved through plasmon-assisted electric field concentration effects. Simulation results show about 50 times light absorption enhancement for 850 nm light due to improved optical signal propagation through the nano-gratings.

In this paper, we use the finite difference timedomain (FDTD) method to optimize the light absorption of an ultrafast plasmonic GaAs metal-semiconductor-metal photodetector (MSM-PD) employing metal nano-gratings. The MSM-PD is optimized geometrically, leading to improved light absorption near the designed wavelength of GaAs through plasmon-assisted electric and magnetic field concentration through a subwavelength aperture. Simulation results show up to 10-times light absorption enhancement at 867 nm due to surface plasmon polaritons (SPPs) propagation through the metal nano-grating, in comparison to conventional MSM-PD.

In this paper, we adopt the finite difference time-domain (FDTD) method to optimize the absorption of a novel metal-semiconductor-metal photodetector (MSM-PD) structure based on the use of a double-layer nanostructured metal grating. The metal fingers of the MSM-PDs are etched with appropriate depths to maximize light absorption through plasmonic effects. Simulation results show 40 times enhancement in 980 nm light trapping due to extraordinary optical signal propagation through the nanostructured double-metal grating, in comparison to conventional MSM-PDs.

Semiconductor laser is an important optical source used in various applications. A model of laser is required to simulate its performance before fabrication. In the past few decades, many laser models are developed using different types of modeling techniques. Analyses of these lasers are normally carried out by numerically solving the rate equations. Circuit simulation is one of the tools for the design and analysis of the relatively complex circuits such as semiconductor laser, which can include the parasitic and driver Circuitry. In this thesis four different types of laser structures, namely double heterostructure (DH), quantum well (QW), vertical cavity (VC) and hybrid bistable laser are developed. These circuit models are analyzed using PSPICE circuit Simulator. large and small signal circuit models for double heterostructure laser diodes are developed from the rate equations. The models include both single and multi mode operations of the DH laser. The effects of coupling coefficient, parasitics circuit, driver circuit and gain compression are studied in detail. The l-I curve, transient response and frequency response analysis are studied and it shows good agreement with the experimental results. A circuit model of quantum well laser based on the 3 level rate equations is also developed. The temperature effect on the laser behaviour is studied by incorporating equivalent thermal circuit model into the laser model. The effects of temperature, leakage current and heat dissipation are also considered in the equivalent thermal model. The effect of bias current on the transient behaviour of QW laser at various temperatures is studied. It is found that the laser performance is a function of separate confinement heterostructure (SCH) region length. It is observed that the modulation response of QW laser with shorter separate confinement heterostructure length is more sensitive to the temperature variation. The effect of temperature on multimode and frequency respons

Semiconductor laser is an important optical source used in various applications. A model of laser is required to simulate its performance before fabrication. In the past few decades, many laser models are developed using different types of modeling techniques. Analyses of these lasers are normally carried out by numerically solving the rate equations. Circuit simulation is one of the tools for the design and analysis of the relatively complex circuits such as semiconductor laser, which can include the parasitic and driver Circuitry. In this thesis four different types of laser structures, namely double heterostructure (DH), quantum well (QW), vertical cavity (VC) and hybrid bistable laser are developed. These circuit models are analyzed using PSPICE circuit Simulator. large and small signal circuit models for double heterostructure laser diodes are developed from the rate equations. The models include both single and multi mode operations of the DH laser. The effects of coupling coefficient, parasitics circuit, driver circuit and gain compression are studied in detail. The l-I curve, transient response and frequency response analysis are studied and it shows good agreement with the experimental results. A circuit model of quantum well laser based on the 3 level rate equations is also developed. The temperature effect on the laser behaviour is studied by incorporating equivalent thermal circuit model into the laser model. The effects of temperature, leakage current and heat dissipation are also considered in the equivalent thermal model. The effect of bias current on the transient behaviour of QW laser at various temperatures is studied. It is found that the laser performance is a function of separate confinement heterostructure (SCH) region length. It is observed that the modulation response of QW laser with shorter separate confinement heterostructure length is more sensitive to the temperature variation. The effect of temperature on multimode and frequency respons

U.S. Navy and commercial ships have been lucrative targets for terrorist organizations. Realizing that ships are most vulnerable while in-port, adequate measures must be employed by port facilities to ensure vessel security. Commercial and naval ports have been set as a national priority in Homeland Security Presidential Directive 13. A successful terrorist strike against a port could produce long-term economic impact. In an attempt to develop a system of systems to prevent and defeat terrorist attacks against foreign and domestic ports, this study approached the threat from three different aspects: terrestrial, seaborne, and internal. This report uses the Systems Engineering Design Process to define the problem, generate alternatives, model scenarios, and analyze results to produce feasible and cost-effective solutions. No single system can address all issues prevalent in the port security problem. The recommended solutions individually address specific threats, namely vehicle-borne improvised explosive devices, small boat swarm tactics, importation of contraband or weapons of mass destruction, and employee sabotage. Although each solution effectively increased port security, improved port security measures resulted in greater cost. Some solutions yielded only marginal gain in effectiveness with drastic increases in cost.

A temperature-dependent quantum well laser equivalent circuit model based on three-level rate equations is presented. The model is simulated using an ORCAD PSPICE circuit simulator. The characteristic properties such as threshold current, delay, and frequency response are simulated and compared with the available results. Included are temperature effect, leakage current, and heat dissipation effect on the chip. Threshold current increases, whereas turn on delay and optical output decrease with increasing temperature. An increase in temperature also reduces the operating frequency and resonance peak shifts to higher frequency. It is also observed that the modulation response of a QW laser with shorter separate confinement heterostructure region is more sensitive to the temperature variation.