Electric fencing is commonly used on New Zealand's farms. Modern technology is used in farm management systems to solve old farming problems in a more efficient and simple way. Engineers have researched the use of the electric fence as a communication medium and new technologies based on transmission line theory are used at present to monitor and troubleshoot problems occurring in electric fences. The next stage of the development is to use wireless devices to accomplish those same tasks from remote locations. This project aims to develop a prototype that provides a wireless link between an electric fence and a personal computer in a remote location. This prototype is expected to prove concepts that lead to the future design of useful, marketable products. The project was supported by Gallagher Electronics and is implemented using their existing products where possible.

Continual advancements in technology have led to the development of reliable, efficient and economical farm management systems, many of which utilize electric fences for effective control of farm animals. An electric fence system constitutes a conducting fence structure that is energized by a high voltage signal generated from an electric fence energizer. Modern electric fence energizers employ a pulsed power supply together with an appropriate high voltage charging scheme to generate high voltage pulses that energize the fence structure. The high voltage pulse delivers a non-lethal electric shock to an animal that comes into contact with the fence, and the consequent psychological impact on the animal is such that it is less likely to come into contact with the fence again. The complexity associated with modelling electric fence systems has hindered the development of proper mathematical tools that aid their design and optimization, and as a consequence, electric fence systems are currently designed using empirical rules together with a trial and error design approach. This Thesis therefore aims to fulfil this need by presenting new technologies and mathematical tools that can be used to design both intelligent and optimized electric fence systems. It presents a comprehensive study on electric fencing systems, which includes a detailed mathematical analysis on pulse propagation properties of electric fence networks and the development of high performance fence energizers that incorporates new pulses power supply technologies and high voltage charging schemes. With regard to the pulsed power technologies, two novel topologies with the ability to adapt their output pulse shape according to the fence conditions are proposed. The performance of these technologies is analyzed mathematically, and verified experimentally. In comparison to the existing fence energizer technology, energizers that are based on the proposed pulsed power supply designs are superior in performance. Furthermore, a novel Buck-Boost pushpull parallel-resonant converter technique, which is suitable for charging high voltage storage capacitors in an energizer, is also presented. The proposed technique allows for the push-pull parallel-resonant converter to operate with a frequency dependent variable voltage gain over a wide load range while maintaining zero voltage switching (ZVS). The operation of the converter is analyzed mathematically and verified experimentally to validate the proposed technique. In order to gain an insight into the propagation characteristics of electric fence networks, the Thesis presents a comprehensive mathematical model. The model uses the propagation properties of fence networks with frequency dependent distributed line parameters to obtain analytical solutions for the propagation function in the frequency-domain. As these analytical solutions are complex in nature, they are solved numerically to obtain time-domain solutions, the accuracy of which are verified through experiments and simulations. The mathematical tools and new technologies proposed in the thesis can be used to design electric fence systems that are more efficient and effective than the existing systems. In addition, the tools proposed are also expected to aid the design of electric fence based communication channels for intelligent farm management systems.

White-tailed deer (Odocoileus virginianus) have been intensively studied across their range. However, many aspects of the white-tailed deer’s ecology have not been studied or are difficult to study. The advent of global positioning system (GPS) collar technology and molecular genetics techniques now allows researchers to collect fine-scale and cryptic phenomena. In addition, selective harvest of male white-tailed deer, based on antler size, has not been critically evaluated. Thus, development and use of quantitative genetics models will be useful for elucidating the effects of selective harvest on mean population antler size. I used GPS collar technology to further understand white-tailed deer movement ecology. First, I determined the efficacy and influence of a high-tensile electric fence (HTEF) on deer movements. The HTEF controlled deer movements when properly maintained and had little influence on deer spatial dynamics, making it a safe and cost-effective alternative to traditional fencing. Second, I studied fine-scale deer movements using GPS collars collecting locations every 15 minutes. Hourly deer movements were greatest in the morning and evening. Parturition and rut influenced movements of females and males, respectively whereas weather and moon phase had minimal influence on movements. Molecular genetics techniques are becoming more widespread and accessible, which may allow insight into the link between genetics and antler size. I found deer in 3 diverse populations from Mississippi, Oklahoma and Texas were relatively heterozygous and unrelated. Groups of deer with similar antler characteristics did not appear to be inbred or share common ancestors. In addition, there was not a strong link between individual multi-locus heterozygosity and antler points or score. Selective harvest has been implicated in causing negative evolutionary and biological responses in several ungulate species. To better determine how selective harvest (i.e., culling; the removal of deer with inferior antlers) affects white-tailed deer antler size, I used quantitative genetic models to simulate response of deer antlers to selection. In simulated controlled breeding situations response to selection was rapid, resulting in improvement in antler size. In simulated free-ranging populations response of antler size to selection was slow and only resulted in minimal increases in antler points after 20 years.