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With the aim of providing high data rates, the Long Term Evolution (LTE) standard makes use of relaying as one of the important techniques for new mobile networks. LTE will also make use of the Multiple-Input Multiple-Output (MIMO) technique, to improve the trans-mission’s quality in hostile environments and to offer very high data rates. The relay solution in mobile networks planning is a highly used technique in next LTE networks. This technique has the aim of increasing the network coverage and/or capacity and improves the cell edge throughput. The Relay Station (RS) performance depends on its position in the cell, the radio conditions to which the RS and the User Equipment (UE) are subjected, and the RS capability to receive process and forward the information. The aim of this thesis is to conclude about the optimized position in which a RS (from types Amplify and Forward (AF) / Selective Decode and Forward (SDF)) should be placed, with the aim of maximizing the UE throughput. F...

Progress in the terahertz (THz) region of the electromagnetic spectrum is undergoing major advances, with advanced THz sources and detectors being developed at a rapid pace. Yet, ultrafast THz communication is still to be realized, owing to the lack of practical and effective THz modulators. Here, we present a novel ultrafast active THz polarization modulator based on GaAs semiconductor nanowires arranged in a wire-grid configuration. We utilize an optical pump-terahertz probe spectroscopy system and vary the polarization of the optical pump beam to demonstrate ultrafast THz modulation with a switching time of less than 5 ps and a modulation depth of -8 dB. We achieve an extinction of over 13% and a dynamic range of -9 dB, comparable to microsecond-switchable graphene- and metamaterial-based THz modulators, and surpassing the performance of optically switchable carbon nanotube THz polarizers. We show a broad bandwidth for THz modulation between 0.1 and 4 THz. Thus, this work present...

Production of genetically and phenotypically stable plantlets is the main purpose in commercial strawberry tissue culture. In this study, different tissues of Fragaria ananassa cv. Camarosa including stipule, apical meristem, leaf and petiole were cultured in Murashige and Skoog (MS) medium supplemented with different concentrations of N 6-benzyladenine (BA) (0.5, 1, 2, 3 mg/L) and indole-3-butyric acid (IBA) (0.1 and 0.5 mg/L). For apical meristem explants, the best regeneration rate (7.6 shoots per each explant) was obtained in the medium containing 1 mg/L BA and 0.1 mg/L IBA. Whereas stipule explants showed the highest regeneration rate in the medium containing 2 mg/L BA and 0.1 mg/L IBA. For leaf and petiole explants, the medium containing 2 mg/L BA and 0.5 mg/L IBA had the best hormonal combination. To determine the genetic variation, micropropagated plants from different tissue (after 8 subcultures) were analyzed by the inter-simple sequence repeats (ISSR) molecular marker. Among the 18 pre-selected primers, 10 displayed clear, reproducible and informative bands. A total of 88 distinct bands with a polymorphic rate of 46% were produced in the molecular profile of different explants. The highest and the lowest similarity values to maternal plants belonged to stipule and petiole explants with a similarity index of 0.738 and 0.645, respectively. Vitroplants derived from stipule and apical meristem showed the highest genetic stability with respect to maternal plants. With respect to genetic stability and regeneration rate, apical meristem can be recommended as suitable explants with the highest genetic fidelity. The findings of this study could be applied for commercial scale multiplication of strawberry, and also demonstrate that ISSR markers are eligible for detection of somaclonal variations.

I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work.

This research applies the indigenous entrepreneurship model developed at the center for entrepreneurial development at IBA Karachi. This model is based on the pre-effectuation principles and effectuation theory of entrepreneurship. The model is different from the existing utilitarian models. The model signifies the importance of nation-building and family orientation to pursue an entrepreneurial journey. The efficacy of the model has been tested on a sample of 500 young participants (men and women) during the Entrepreneurship Programs. Effectuation and Pre-effectuation have been tested on a sample of 500 participants (including both men and women), and Nation-building and Family orientation is tested amongst the sample of women only. The paper reveals the impact of entrepreneurial mindset training and coaching in Karachi and Faisalabad. For the efficacy of the indigenous entrepreneurship model, the research paper presents the sample case studies.

An object-based approach for forest disaster change detection using High Resolution (HR) satellite images is proposed. An automatic feature selection process is used to optimize image segmentation via an original calibration-like procedure. A multitemporal classifi-cation then enables the separation of wind-fall from intact areas based on a new descriptor that depends on the level of fragmentation of the detected regions. The mean shift algorithm was used in both the segmentation and the classification processes. The method was tested on a high resolution Formosat-2 multispectral satellite image pair acquired before and after the Klaus storm. The obtained results are encouraging and the contribution of high resolution images for forest disaster mapping is discussed. 1

The association of the black rot fungus Ciboria batschiana and the chestnut weevil Curculio propinquus was investigated. Insects from a single plantation located in a chestnut area in Viterbo, in the Lazio Region (Italy) were analysed for association with the fungus. Ciboria batschiana was detected in 2 out of 10 adults collected from the ground and 21 out of 22 adults from the trees. Only 33.3% of the larvae were found to be associated to the fungus. The ability of C. propinquus to carry the fungus was confirmed. Its role as a possible vector of this pathogen deserves further study.

An introduction to various topics in neutrino astrophysics is given for students with little prior exposure to this field. We explain neutrino production and propagation in stars, neutrino oscillations, and experimental searches for this effect. We also touch upon the cosmological role of neutrinos. A number of exercises is also included. Contents

I am also grateful to the staff of the Directorate of Water Resources Management-Uganda for their patience and cooperation during my data collection. Thanks go to the management and staff of National Water and Sewerage Corporation for the information and facilitation given. The assistance given by all Government offices visited is also highly appreciated. To my family: Thank you for being so supportive. Finally, I am deeply grateful to God for making this research possible.

I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work.