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An extensive amount of research has been conducted on Radio Frequency IDentification (RFID) in the context of logistics, supply chain and manufacturing. Additionally, marketing opportunities related to RFID usage have been argued to exist. Despite this, limited research has focused on RFID in a marketing context which constitutes the research gap for this study.  A literature review on the subject area yielded an overview of the existing literature within the field. The literature review identified a research gap that constitutes the purpose of this study. The purpose is to investigate the factors influencing the adoption of Radio Frequency IDentification technology and whether it enhances retailers’ marketing opportunities. The study was of a qualitative nature and was conducted through a multiple case study. Data was gathered through semi-structured interviews with four companies. An archival analysis was performed in addition to the interviews. The interview data reveals that RFID technology adoption still has barriers to overcome, especially in regards to the identified marketing opportunities. Based on the conclusions of this study recommendations for managerial implications were formed. The findings of the study were able to support previous research stating that the main challenge for RFID adoption is the cost of the equipment. However, the previously identified marketing opportunities were not fully supported by the interviewed companies, thus, this area of research needs to be developed further.

Over the past several decades, experimental studies of the organisation of spatial frequency (SF) preference in mammalian visual cortex (V1) have reported a wide variety of conflicting results. A consensus now appears to be emerging that in the superficial layers SF is mapped continuously across the cortical surface. However, other evidence suggests that SF may differ systematically with cortical depth, at least in layer 4, where the magnocellular (M) and parvocellular (P) pathway afferents terminate in different sublaminae. It is not yet clear whether the topographic organisation for SF observed in the superficial layers is maintained throughout the input layers as well, or whether there is a switch from a laminar to a topographic organisation along the vertical dimension in V1. I present results from two alternative self-organising computational models of V1 that receive natural image inputs through multiple SF channels in the LGN, differing in whether they develop laminar or topographic organisation in layer 4. Both models lead to topographic organisation for orientation (OR) and SF preference in upper layers, consistent with current experimental evidence. The results suggest that in either case separate sub-populations of neurons are required to obtain a wide range of SF preference from Hebbian learning of natural images. These models show that a laminar organisation for SF preference can coexist with a topographic, columnar organisation for orientation, and that the columnar organisation for orientation is dependent upon inter-laminar feedback. These results help clarify and explain the wide range of SF results reported in previous studies.

Three main issues are explored in this thesis—volatility measurement, volatility spillover and large-dimension covariance matrices. For the first question of volatility measurement, this thesis compares two newly-proposed, high-frequency volatility measurement models, namely realized volatility and realized range-based volatility. It does so in the aim of trying to use empirical results to assess whether one volatility model is better than the other. The realized volatility model and realized range-based volatility model are compared based on three markets, five forecast models, two data frequencies and two volatility proxies, making sixty scenarios in total. Seven different loss functions are also used for the evaluation tests. This necessarily ensures that the empirical results are highly robust. After making some simple adjustments to the original realized range-based volatility, this thesis concludes that it is clear that the scaled realized range-based volatility model outperforms the realized volatility model. For the second research question on volatility spillover, realized range-based volatility and realized volatility models are employed to study the volatility spillover among the S&P 500 index markets, with the aim of finding out empirically whether volatility spillover exists between the markets. Volatility spillover is divided into the two categories of statistically significant volatility spillover and economically significant volatility spillover. Economically significant spillover is defined as spillover that can help forecast the volatility of another market, and is therefore a more powerful measurement than statistically significant spillover. The findings show that, in reality, the existence of volatility spillover depends on the choice of model, choice of volatility proxy and value of parameters used. The third and final research question in this thesis involves the comparison of various large-dimension multivariate models. The main contribution made by this specific study is threefold. First, a number of good performance multivariate volatility models are introduced by adjusting some commonly used models. Second, different models and various choices of parameters for these models are tested based on 26 currency pairs. Third, the evaluation criteria adopted possess much more practical implications than those used in most other papers on this subject area.

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / With the development of the airborne telemetry technique, it will be demanded that the transmitting sets on the missiles are more reliable and smaller. A frequency modulation (FM) oscillator stabilized with a dielectric resonator (DR), which can operates in the S-band directly, is presented. The FM oscillator is of simple circuit, reliable operation in the stabilization, small size, light weight and low cost. It will have a certain prospect of application in the airborne telemetry transmitting sets.

This thesis was a continuation in part of a NPS project relating to microwave wireless power transmission for micro air vehicles (MAVs). The concept of using microwaves for transferring power in free space has existed since the beginning of the 20th century. The emphasis of this thesis is the experimental study of powering micro air vehicles via the use of using a microstrip rectenna (rectifying antenna) at 10 GHz. A microstrip rectenna was built and experiments were conducted to measure the efficiency of the rectenna elements. The conversion of radio frequency (RF) power into usable DC power was performed by a rectenna. Its function could be broken down into the following four stages: reception of radio frequency (RF) power, prerectification filtering, rectification, and post-rectification filtering. A rectenna model based on past research by NPS students was simulated, built, and tested. The analysis and findings of the rectenna model were presented, with suggested improvements highlighted. / Technology Agency author (civilian).

Optically pumped semiconductor vertical external cavity surface emitting lasers (VECSEL) were first demonstrated in the mid 1990's. Due to the unique design properties of extended cavity lasers VECSELs have been able to provide tunable, high-output powers while maintaining excellent beam quality. These features offer a wide range of possible applications in areas such as medicine, spectroscopy, defense, imaging, communications and entertainment. Nowadays, newly developed VECSELs, cover the spectral regions from red (600 nm) to around 5 µm. By taking the advantage of the open cavity design, the emission can be further expanded to UV or THz regions by the means of intracavity nonlinear frequency generation. The objective of this dissertation is to investigate and extend the capabilities of high-power VECSELs by utilizing novel nonlinear conversion techniques. Optically pumped VECSELs based on GaAs semiconductor heterostructures have been demonstrated to provide exceptionally high output powers covering the 900 to 1200 nm spectral region with diffraction limited beam quality. The free space cavity design allows for access to the high intracavity circulating powers where high efficiency nonlinear frequency conversions and wavelength tuning can be obtained. As an introduction, this dissertation consists of a brief history of the development of VECSELs as well as wafer design, chip fabrication and resonator cavity design for optimal frequency conversion. Specifically, the different types of laser cavities such as: linear cavity, V-shaped cavity and patented T-shaped cavity are described, since their optimization is crucial for transverse mode quality, stability, tunability and efficient frequency conversion. All types of nonlinear conversions such as second harmonic, sum frequency and difference frequency generation are discussed in extensive detail. The theoretical simulation and the development of the high-power, tunable blue and green VECSEL by the means of type I second harmonic generation in a V- cavity is presented. Tens of watts of output power for both blue and green wavelengths prove the viability for VECSELs to replace the other types of lasers currently used for applications in laser light shows, for Ti:Sapphire pumping, and for medical applications such as laser skin resurfacing. The novel, recently patented, two-chip T-cavity configuration allowing for spatial overlap of two, separate VECSEL cavities is described in detail. This type of setup is further used to demonstrate type II sum frequency generation to green with multi-watt output, and the full potential of the T-cavity is utilized by achieving type II difference frequency generation to the mid-IR spectral region. The tunable output around 5.4 µm with over 10 mW power is showcased. In the same manner the first attempts to generate THz radiation are discussed. Finally, a slightly modified T-cavity VECSEL is used to reach the UV spectral regions thanks to type I fourth harmonic generation. Over 100 mW at around 265 nm is obtained in a setup which utilizes no stabilization techniques. The dissertation demonstrates the flexibility of the VECSEL in achieving broad spectral coverage and thus its potential for a wide range of applications.

Retinal blur experienced by myopes during near work has been linked to myopia development and progression. Whether poor responses to blur signals are due to poor perceptual blur sensitivity (subjective depth of focus), poor neural accommodation responses (objective depth of focus) to blur or optical differences such as higher order aberrations making blur detection difficult is yet unclear. This study investigates whether myopes respond to blur differently compared to emmetropes and whether filtering spatial frequencies in reading text influence accommodation responses. Accommodative functions were investigated using spatial frequency filtered text targets of two different sizes (N10 and N20). Monocular objective depth of focus (DOF), accommodative microfluctuations, and dynamic accommodation were measured. Subjective DOF after cycloplegia was also recorded with the same targets. Higher order aberration measurements explored optical contributions to blur. Peripheral refraction and accommodative lag were also measured to consider how in combination they might increase peripheral retinal blur for near tasks. Results showed that myopes demonstrated larger subjective DOF. Subjective DOF was larger when viewing the peak text spatial frequency in both refractive error groups. The optimum focus was more myopic for text peak spatial frequencies. Levels of spherical aberration were correlated with the point of optimum focus. Objective DOF and accommodative microfluctuations were larger in myopes when viewing the peak text spatial frequencies. Dynamic accommodation showed that while myopes were not poorer at initiating accommodation responses they had longer positive response times. Accommodative lag, although not different in myopes, increases the peripheral hyperopic blur experienced for near tasks. Conclusion: Myopes were poorer at using retinal blur cues to refine accommodation responses especially when viewing peak text spatial frequencies. Larger positive response times, DOF and accommodative microfluctuations in myopes resulted in accommodative error and hyperopic blur for near tasks. Spherical aberration, previously thought to provide a myopigenic stimulus, was not different between refractive groups and is unlikely to be large enough to enhance DOF during naturalistic viewing. Blur adaptation studies might consider using peak text spatial frequencies as adaptation targets to reduce accommodation differences in myopes and emmetropes. Optical treatment strategies aimed at correcting peripheral refraction to control myopia should consider the combined effect of accommodative lag which increases levels of hyperopic peripheral blur experienced by myopes.

The purpose of this study is to attempt to determine what influence configuration and/or letter sequence have on the recognition thresholds of words. It is felt that low configuration and/or rare letter sequences will result in lower recognition thresholds, while high configuration and/or common letter sequence will result in higher recognition thresholds when stimulus words are presented to subjects by means of a tachistoscope.