Widespread adoption of phased array technologies has been hindered primarily by the high cost associated Transmitter/Receiver (T/R) modules. In conventional phased arrays, these vital elements often comprise up to fifty-percent of the entire array's expense. Recent development of a new type of phased array - the Electronically Steerable Passive Array Radiator (ESPAR) - is underway at laboratories around the globe. This innovative concept utilizes mutual coupling to excite neighboring (passive) elements placed in the near field of a center-driven (active) radiator. Using this method, T/R modules are only required for the active radiators. The radiation pattern of an ESP AR is controlled electronically by means of variable reactive loading of the passive antenna elements. In order to attain the full range of beam steering offered by this array, a broad range of reactance is required at the input port of each passive antenna. This thesis presents a varactor-based reactive network design that can accurately and reliably produce a wide range of reactance. The purpose of this research was to design a network compatible with the requirements of the ESP AR phased array, which is in development at the Antennas, RF, and Microwave Integrated Systems CARMI) laboratory at the University of Central Florida. To this end, an elaborate survey weighing different varactor-based reactive network and DC bias tee designs was conducted. This study took into account the practical issues and limiting factors that arose during design and implementation of such a network. While this specific network design was constrained to operate at 3 GHz, the proposed design methodology may be applied to realize reactive networks at other frequencies. This flexibility allows incorporation into similar ESPAR's and a plethora of other relevant devices.

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Le biais de sélection par rapport au sexe (ou biais de sexe) représente une différence systématique des proportions d’hommes et de femmes entre un échantillon de participants et leur population, ce qui peut miner la validité d’une étude. La recherche sur le stress humain est susceptible au biais de sexe étant donné la présence de facteurs y étant généralement associés, principalement les protocoles invasifs – contenant des éléments douloureux, inconfortables ou menaçants pour les participants. La présente étude a vérifié si les proportions d’hommes et de femmes des études sur le stress varient selon 1) le niveau d’invasion d’une étude en stress (invasif ou non invasif) et selon 2) des facteurs exploratoires (p. ex. pays, méthode de recrutement). Deux domaines hors stress possédant des protocoles invasifs (douleur expérimentale) et non invasifs (mémoire) ont été utilisés comme domaines contrôles. Dans cette enquête transversale de la littérature, les proportions d’hommes et de femmes ont été recueillies dans 324 études contenant des protocoles invasifs ou non invasifs, représentant un total de 23 611 participants, dont 42,18 % d’hommes. La représentativité des sexes a varié selon le niveau d’invasion dans les domaines du stress et hors stress, les hommes davantage représentés dans les études invasives que dans les études non invasives. Les résultats indiquent que les facteurs exploratoires analysés peuvent tous être associés au sexe. Cette étude a identifié la présence de facteurs pouvant provoquer un biais de sexe en recherche sur le stress humain, ouvrant la voie aux recherches souhaitant approfondir la généralisation des résultats. / Sex selection bias (or sex bias) refers to a systematic difference in the proportions of men and women between a sample of participants and their population, which may undermine the validity of a study. Human stress research is vulnerable to sex bias, given the presence of factors typically associated with it, primarily invasive protocols — containing painful, uncomfortable, or threatening elements for participants. The present study has verified whether the proportions of men and women in stress studies differ by 1) the invasiveness of a study (invasive or non-invasive) and by 2) exploratory factors (e.g. country, recruitment method). Two non-stress domains with invasive (experimental pain) and non-invasive (memory) protocols were used as control domains. In a cross-sectional survey of the literature, the proportions of men and women were collected from 324 studies containing invasive or non-invasive protocols, representing a total of 23 611 participants, 42,18 % of whom were men. Sex representativeness differed across invasiveness levels in both the stress and non-stress domains with men being more represented in invasive than in non-invasive studies. Results indicate that the exploratory factors analyzed may all be associated with sex. This study identified the presence of factors that may cause sex bias in human stress research, opening the door to research wishing to further investigate the generalizability of results.

Master of Science / Food Science Institute / Delores Chambers / Psychographic Questionnaires: A Comparative Review of Structures and Scales In recent years there has been a growing trend toward integrating psychographic profiles into sensory studies with the aim of more holistically explaining consumer segmentation and preferences. With this shift in approach have come questions on the nature of psychographic scales and the theoretical implications of their structure. Given the plethora of existing psychographic scales in common practice, the purpose of this review is to give a concise overview in the breadth of structures, with the aim of helping sensory researchers identify the most appropriate scale for their needs. The review begins with a critical comparison of the three most common scale classes: Likert, Semantic Differential, and Behavioral Frequency, and their relative advantages and disadvantages. Following that, a review of psychographic questionnaire design highlights differences from sensory practices, drawing attention to sources of response bias in specific design typologies which may reduce data quality in a product design.

This thesis contributes to the public finance literature concerned with fiscal sustainability, and consists of an introduction and four stand-alone essays. The first three essays analyse the reasons why governments accumulate large levels of debt. In the first essay, I find that parties that implement fiscal consolidations are punished by the voters in the following election. However, there does not appear to be a rewarding effect for governments that implement fiscal expansions. The second essay, which is co-authored with Rafael Ahlskog, shows how voter opposition to fiscal consolidation is shaped by moral considerations and feelings of personal responsibility. More precisely, we argue that voters are more likely to refuse fiscal consolidation when they do not feel responsible for the public debt. The third essay argues that misperceptions about the business cycle would have caused fiscal problems even if policy-making was conducted by independent experts. According to my estimates, biased projections have weakened annual budget balances by approximately one per cent of GDP. In the fourth essay, I argue that budgetary mechanisms created to improve fiscal discipline have a bias toward a reduced public sector. Because discretionary decisions are usually required to adjust public expenditures to price and wage increases, periods of rapid growth have repeatedly caused the welfare state to shrink. I use the introduction to discuss the commonalities between the essays and to situate the field of public finance in a broader, historical context.

Variable importance measures for random forests have been receiving increased attention as a means of variable selection in many classification tasks in bioinformatics and related scientific fields, for instance to select a subset of genetic markers relevant for the prediction of a certain disease. We show that random forest variable importance measures are a sensible means for variable selection in many applications, but are not reliable in situations where potential predictor variables vary in their scale level or their number of categories. This is particularly important in genomics and computational biology, where predictors often include variables of different types. Simulation studies are presented illustrating that, when random forest variable importance measures are used with data of varying types, the results are misleading because suboptimal predictor variables may be artificially preferred in variable selection. The two mechanisms underlying this deficiency are biased variable selection in the individual classification trees used to build the random forest on one hand, and effects induced by bootstrap sampling with replacement on the other hand. We propose to employ an alternative implementation of random forests, that provides unbiased variable selection in the individual classification trees. When this method is applied using subsampling without replacement, the resulting variable importance measures can be used reliably for variable selection even in situations where the potential predictor variables vary in their scale level or their number of categories. The usage of both random forest algorithms and their variable importance measures in the R system for statistical computing is illustrated and documented thoroughly in an application re-analysing data from a study on RNA editing. Therefore the suggested method can be applied straightforwardly by scientists in bioinformatics research. (author's abstract) / Series: Research Report Series / Department of Statistics and Mathematics

The present rapid increase in the number of space missions demands a decrease in the cost of satellite equipment, but also requires the development of instruments that have low power consumption, low weight, and small size.Anisotropic magnetoresistance (AMR) sensors can answer these needs on account of their small size, weight, and power consumption. AMR sensors also produce lower noise than either giant magnetoresistance (GMR) or tunnel magnetoresistance (TMR) devices and are thus more suitable for space applications.The type of AMR sensor developed in this study was a Planar Hall EffectBridge (PHEB) sensor. The FM layer was also coupled with an AFM layer in order to fix the internal magnetization of the FM layer.One technique that was employed in order to meet the low-noise requirement was to make the FM layer thicker than has previously been attempted.In doing so, the exchange bias field between the AFM layer and the FMlayer is no longer high enough to bias the thicker FM layer, so in order to correct this unwanted effect, the material stack was upgraded to two AFM–FM interfaces. With this configuration, it became possible to increase the exchange field by up to 60%. Stronger exchange bias leads to a thicker FMlayer and so to lower noise in the device performance. Another strategy that was used to lower the resistance of the device was to implement an NiFeX alloy instead of the standard NiFe. NiFeX consists of an alloy of NiFe andCu, Ag, or Au; the last of these is known to have very low resistivity.This solution leads to a significant lowering of the device’s resistance. A recent technological advance used to fabricate devices with lower resistance is to deposit a multilayer of AFM–FM.

The aim of this master’s thesis is to examine how gender is produced in a contemporary technological sphere. I am examining a department called MST within the School of Electrical Engineering at The Royal Institute of Technology (KTH) primarily by focus group interviews and in depth interviews with a doing gender perspective. I also carry out participant observations for additional background information. I argue from a gender studies perspective that KTH as a technological institution and workplace is reproducing ideals that confirms men as norm. Furthermore, I suggest that the technical sphere and historically traditional (male) gendered environment that which KTH represents, embodies and reproduces, makes it more challenging for female PhD-students to compete against their male counterparts when it comes to gaining recognition than it is vice versa. I am studying the awareness of gender norms in a technical milieu as well as thoughts about the daily negotiations and biased representations of gender on postgraduate/research level among the female PhD-students at MST. Moreover, I suggest that there are certain connotations with and cultural conceptions of what it means to be and to work as an engineer.

Objectives: This study sought to determine whether a computerised cognitive bias modification programme could be effective within a waiting-room setting for parents accompanying their children to CAMHS appointments. The primary objectives were to determine whether detectable changes to participants' emotion recognition could be observed in this setting, and whether this approach would be acceptable to the population. Secondary measures investigated whether the programme would lead to changes in participants' affect or changes in parents' appraisals of difficulties with children. Methods: A computerised emotion recognition training task was delivered to all participants during four weekly sessions. Participants in the experimental condition (n=17) received feedback aiming to shift their detection of positive facial emotions, while those in the control condition (n=14) received feedback which was not designed to elicit any shift in emotion detection. Results: Positive shifts in emotion recognition were observed in the experimental group, although no changes were observed in secondary measures in either control or experimental groups. Qualitative data indicated that the programme was acceptable and appropriately constructed. Conclusion: This study demonstrates that cognitive bias modification is possible within a waiting-room setting, although the extent to which this can lead to clinically significant improvements in mood or relationships remains uncertain. This work has implications for emotion recognition interventions for clinical populations known to present with negative emotional biases (e.g. anxiety and depression) and represents an important first research step towards developing interventions to improve parent-child relationships.