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The present Master Thesis analyzes the DVB-H radio Frequency Network Planning problematic, studying the influence of a propagation model used in the calculation of network coverage. In this way, the aim of this work is the design of a procedure and algorithm to adjust a propagation model considering measurement campaigns performed in different environments (dense-urban, urban, sub-urban and rural). The methodology relies on the adjustment of the Xia-Bertoni propagation model parameters using the Least Mean Square (LMS) method, considering the collected measurements and the simulation model parameters obtained from a Geographic Information System (GIS). Coverage simulations and measurement results are compared using a 3-Dimensional city model (terrain and buildings) for different terrain topologies (flat, hills and canyons) and environments. The resulting adjusted model has been tested and compared with other common models (COST231 and Okumura-Hata) using specific metrics, thus proving its validity for different frequencies, environments and terrain topologies. In order to validate the procedure and designed algorithm, this Master Thesis gathers real data from measurement campaigns carried out in different cities: Gävle (Sweden), Bucaramanga (Colombia), Valencia (Spain) and Munich (Germany). Besides, this work provides an insight on best practices to perform measurement campaigns. The outcome of this work is a useful tool in radio network planning for DVB-H systems, which ensures reliable results in all environments and terrain topologies.

Research was undertaken to optimize propagation of the southern China native Camptotheca acuminata Decaisne, source of the medicinal compound camptothecin that is used in the treatment of multiple forms of cancer and other diseases. The study focused on cutting propagation, micropropagation, and seed storage. Softwood cuttings of C. acuminata rooted readily in intermittent mist (4 sec on every 6 min.) in coarse vermiculite when treated with K-IBA (indolebutyric acid, potassium salt) quick dips ranging from 4.14 mM to 37.3 mM, with a 29.0 mM quick dip (5 sec.) promoting 82% rooting with little foliar damage. Actively growing shoot tip explants were tissue cultured on media containing Murashige and Skoog, Gamborg's B5, and Woody Plant Medium (WPM) salts in factorial combinations with BA (benzyladenine). WPM containing 4.44 μM BA promoted excellent shoot proliferation; microcuttings were rooted, acclimated, and grown in the greenhouse. Seeds stored in polyethylene bags in a refrigerator (4°C) or freezer (-20°C) maintained good germination (81% and 80%, respectively) while seeds stored at room temperature (25°C) in polyethylene bags lost germination ability quickly (58%) after one year of storage. C. acuminata is readily adaptable to modern nursery techniques for either vegetative or seed propagation.

The current options for wireless signal prediction in indoor scenarios generally either lack precision or require immense computational resources. Thus, a new method is proposed that attempts to consolidate the desired accuracy with an easy to implement and time efficient scheme. This work identifies and takes advantage of dominant physical qualities of indoor environments to solve indoor channel problems using a hybrid of numerical and analytical approaches. Specifically, the guiding effect of hallway structures is investigated as they allow electromagnetic fields to propagate with relatively low attenuation. Combining waveguide mode analysis and rigorous numerical techniques, the proposed prediction model computes the hallway fields in a large building floorplan both quickly and with good accuracy in comparison to full finite-difference simulations. Signal measurement data will also be used to verify the applicability of the model.

In this report a radar model is modeled and implemented in a simulation framework called Flames. The focus is to investigate how and if electromagnetic waves emitted from the radar antenna can be simulated by different methods and how these methods can be implemented to work in real-time simulations. The radar model developed in this report is based on ray tracing and ray propagation techniques developed by the author. The model considers varying refractive indices that describes both standard atmospheres and atmospheres where ducting occur. Preparatory studies are also made to model ground reflection by ray tracing techniques. Other simulation techniques, such as the Finite-Difference Time-Domain method and the Split-Step Parabolic Equation method, are furthermore considered for radar simulation applications. The results show that ray tracing in conjunction with geometrical optics is a valid method for simulating electromagnetic waves in simple atmosphere models.

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Tissue-cultured shoots and plantlets usually have leaves with non-functional, open stomata and little epicuticular and cuticular wax, resulting in excess evapotranspiration after transplantation. Various strategies were evaluated to decrease ex vitro acclimatization difficulties for 'Silvan' blackberry, including transplanting unrooted shoots, increasing the medium agar concentration from 6 to 9 or 12 g/l and diluting the basal medium. Increased medium agar concentrations and medium dilution did not improve survival or growth. Stomatal function resumed sooner in new leaves of plantlets than shoots. High relative humidity ($>$95%) and low light intensity (90 $ mu$mol s$ sp{-1}$ m$ sp{-2}$) negatively affected stomatal closure both on acclimatizing transplants and greenhouse-grown plants. Guard cells developed on leaves in vitro were physiologically active but had apparent anatomical abnormalities that inhibited closure. A rapid clearing and staining method was developed for examination of foliar morphology using intact in vitro blackberry (Rubus sp. 'Silvan') and strawberry (Fragaria x ananassa Duch. 'Totem') plantlets and sections of greenhouse-grown 'Silvan' and 'Totem' leaves. This method involved three steps: (1) removing the chlorophyll by autoclaving in 80% ethanol; (2) dissolution of the protoplasm using 5% NaOH at 80$ sp circ$C; (3) post-alkali treatment with 75% bleach (4.5% NaClO) at room temperature for tissue-cultured plantlets and at 55$ sp circ$C for greenhouse-grown leaves. Aqueous safranin (10 mg/l) was used for staining.

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