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In this paper, a mathematical model is designed for THz generation from a nonlinear random medium. Using nonlinear optics and Maxwell’s equations a set of nonlinear wave equations are derived to give scattered electromagnetic fields from an inhomogeneous medium. First, the analysis is done with second order nonlinearity. Its scattering parameters are calculated for THz radiation. Secondly, third order nonlinearity is described in terms of the coupling of Scalar and vector field components of nonlinear wave equations. The coupling of waves results in soliton generation. Multiple nonlinear interaction in the medium also gives wide bandwidth. Speed and high bandwidth is a demand of future networks. Hence a mathematical proof is implemented for THz antennas using SHG (Second harmonic generation) and THG (Third harmonic generation) materials. These antennas are designed and simulated using GaAs as a SHG material, and Graphene with SiO2 substrate as a THG material. GaAs is used as a substrate, which radiates at 524.8 GHz giving a high bandwidth of 25 GHz. Similarly, Graphene patch antenna with SiO2 substrate radiates in THz region at 3.5THz giving very high bandwidth of 2.5THz.

Photo-lithographic stepper systems are used for manufacturing of integrated chips(IC). For incorporating more functionality and having more space chip manufacturing industries invest heavily to reduce the size of the structures on the chips. This directly requires the stepper system to operate in nanometer scale resolution. To achieve such high accuracy, the stepper system should be isolated from the external vibrations. Isolators are the auxiliary systems that protect the device from floor vibrations. In order to better understand how to tweak isolator components to boost the vibration isolation performance a parameterized multi body model of the system is the first step. From a system theoretical perspective, estimating the parameters of such a multi-body model is a problem on gray-box system identification. The state-of-the art approaches in this field estimates both the state transformation matrix and the system parameters. This increases the number of decision variables in the optimization problem. Very few results exist in which more than 6 system parameters have been estimated accurately. In this thesis we develop a framework for gray-box system identification comprising of PBSIDopt algorithm and H-infinity static output feedback synthesis. This approach bypasses the estimation of state transformation matrix. Also this optimization addresses the input output behavior directly which makes it conceptually simpler. We also explain how to judge whether the framework has estimated the parameters such that the input-output behavior of the system is captured. Our simulation results suggest that to estimate the 16 system parameters very accurately, precise knowledge of the inertial properties of the system is required. Nevertheless, there are other applications within vibration isolation where a multi body model which explains the data is sufficient. We expect our framework to aid the engineers at Zeiss for such applications., Mechanical, Maritime and Materials Engineering, Delft Center for Systems and Control

We undertook a comprehensive study of Latrunculia in New Zealand to determine the relationship between taxonomic, environmental, and chemical variation within the genus. Sponges were collected from five locations around New Zealand: Three Kings Islands, Tutukaka, Wellington, Kaikoura, and Doubtful Sound. Allozyme electrophoresis at nine polymorphic loci indicated that sponges from each geographic location were genetically distinct, and that they displayed genetic differences of the magnitude usually associated with reproductively isolated species (Nei's D between locations =0.375-2.476). Additionally, the comparisons revealed that the green and brown colour morphs of Latrunculia that are sympatric at Three Kings Islands and Kaikoura are distinct from each other, and that there are two genetic groups within the green sponges in Doubtful Sound. On the basis of genetic data we conclude that there are at least eight species of Latrunculia in New Zealand waters, not one to four as had been previously thought. Morphological comparisons of the eight genetic species based on skeletal characters (i.e. skeletal organisation of the choanosome, spicule composition, size, and geometry) indicated that the eight Latrunculia species fell into only two morphological groups that could be easily diagnosed on the basis of discorhabd type. Within these two primary morphological groups, skeletal characteristics among the eight species largely overlap and are not diagnostic. These findings emphasise the limitations of traditional taxonomic methods based solely on skeletal characters for distinguishing species of Latrunculia. However, multivariate analysis (MANOVA and CDA) based on six measured skeletal variables did reveal significant morphological variation among the species (Pillai's Trace=3.28, F=6.90, P<0.0001), supporting the division of the genus into eight species. Comparisons of chemical extracts from Latrunculia also showed that the amounts of five different bioactive compounds (

We undertook a comprehensive study of Latrunculia in New Zealand to determine the relationship between taxonomic, environmental, and chemical variation within the genus. Sponges were collected from five locations around New Zealand: Three Kings Islands, Tutukaka, Wellington, Kaikoura, and Doubtful Sound. Allozyme electrophoresis at nine polymorphic loci indicated that sponges from each geographic location were genetically distinct, and that they displayed genetic differences of the magnitude usually associated with reproductively isolated species (Nei's D between locations =0.375-2.476). Additionally, the comparisons revealed that the green and brown colour morphs of Latrunculia that are sympatric at Three Kings Islands and Kaikoura are distinct from each other, and that there are two genetic groups within the green sponges in Doubtful Sound. On the basis of genetic data we conclude that there are at least eight species of Latrunculia in New Zealand waters, not one to four as had been previously thought. Morphological comparisons of the eight genetic species based on skeletal characters (i.e. skeletal organisation of the choanosome, spicule composition, size, and geometry) indicated that the eight Latrunculia species fell into only two morphological groups that could be easily diagnosed on the basis of discorhabd type. Within these two primary morphological groups, skeletal characteristics among the eight species largely overlap and are not diagnostic. These findings emphasise the limitations of traditional taxonomic methods based solely on skeletal characters for distinguishing species of Latrunculia. However, multivariate analysis (MANOVA and CDA) based on six measured skeletal variables did reveal significant morphological variation among the species (Pillai's Trace=3.28, F=6.90, P<0.0001), supporting the division of the genus into eight species. Comparisons of chemical extracts from Latrunculia also showed that the amounts of five different bioactive compounds (