The design and construction of an electronically beam steered phased array antenna : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physics at Massey University

The design and construction of a simple beam steered phased array antenna was undertaken to demonstrate the operational principles behind such devices. The antenna can be used as a receiver or transmitter, however power requirements dictated that the antenna be tested as a receiver. The design is modular to allow for redevelopment without complete reconstruction. The array is made up of the control module, voltage controlled attenuators and a phase shifting unit. The antenna consists of 16 quarter wave monopoles arranged in a 4X4 square array on an aluminium ground plane. Practical considerations lead to a carrier frequency of 200 MHz. The heart of a phased array antenna is the phase shifting device. This device controls the direction in which the main radiation lobe propagates. Several phase shifting principles were investigated but time did not allow for an exhaustive investigation of every kind of phase shifter. Initially, a relatively new and novel approach was attempted. When this proved to be unachievable a more traditional (but far less elegant) method was used. During the phase shifting process, the signal necessarily suffers attenuation as well as the designed phase shift, consequently it is necessary to tailor the signal amplitudes of each array element. The required amplitude control is achieved through the use of 16 voltage controlled attenuators. A computer package is used to control the phase shifter and attenuators. The design of this package depends on only three factors. The first is the interface between the hardware and the computer (via a serial port in this case). The second factor is the type of control signal the phase shifter and attenuators respond to (in this case a dc voltage). The third factor is the range of voltage required for the phase shifter and attenuators so that their full range can be utilised. This is realised through the use of a microprocessor, a "sample and hold" circuit and several D/A converters. The antenna and computer control package are essentially independent of each other. If an 8 bit digital phase shifter were to be employed later, the hardware could be used to control this with minimal alteration. In this case the advantage of a modular design is apparent. Various parts of the device can be incrementally improved without alteration to the remaining system. Radical change can be accommodated with minimal adjustments

Comprehensive Detection of Genes Causing a Phenotype using Phenotype Sequencing and Pathway Analysis

Discovering all the genetic causes of a phenotype is an important goal in functional genomics. In this paper we combine an experimental design for multiple independent detections of the genetic causes of a phenotype, with a high-throughput sequencing analysis that maximizes sensitivity for comprehensively identifying them. Testing this approach on a set of 24 mutant strains generated for a metabolic phenotype with many known genetic causes, we show that this pathway-based phenotype sequencing analysis greatly improves sensitivity of detection compared with previous methods, and reveals a wide range of pathways that can cause this phenotype. We demonstrate our approach on a metabolic re-engineering phenotype, the PEP/OAA metabolic node in E. coli, which is crucial to a substantial number of metabolic pathways and under renewed interest for biofuel research. Out of 2157 mutations in these strains, pathway-phenoseq discriminated just five gene groups (12 genes) as statistically significant causes of the phenotype. Experimentally, these five gene groups, and the next two high-scoring pathway-phenoseq groups, either have a clear connection to the PEP metabolite level or offer an alternative path of producing oxaloacetate (OAA), and thus clearly explain the phenotype. These high-scoring gene groups also show strong evidence of positive selection pressure, compared with strictly neutral selection in the rest of the genome

An Examination Of Whether Irony And Sarcasm Are Different Terms For The Same Psychological Construct

Researchers have studied counterfactual statements, such as There\u27s not a cloud in the sky! uttered during a violent thunderstorm, both as instances of irony (Jorgensen, Miller & Sperber, 1984; Kreuz & Glucksberg, 1989; Katz & Lee, 1993) and as instances of sarcasm (Gibbs, 1986; Kreuz & Glucksberg, 1989). It is not surprising that some terms are used inconsistently in a young field of investigation such as the psycholinguistics of irony and sarcasm. However. the inconsistent use of the terms irony and sarcasm across different empirical studies is problematic when research participants are asked to judge whether or not counterfactual statements that they read are good examples of the term selected by the researcher. Indeed, to make meaningful inferences from the results of these empirical studies, it is necessary to accept the assumption that irony and sarcasm are different terms for the same psychological construct. The purpose of this dissertation was to test this assumption that irony and sarcasm are, in fact, terms for the same psychological construct. Two experiments were conducted. In experiment one, it was found that the construct associated with sarcasm was affected by a speaker\u27s use of different types of echoic mention whereas the construct associated with irony was not affected. In experiment two, it was found that irony and sarcasm are used differentially with respect to the concept of victim. These findings demonstrate that the terms irony and sarcasm are not interchangeable with regard to their psychological meaning

Islands of Sustainability in Time and Space

We review the economics perspective on sustainable resource use and sustainable development. Under standard conditions, dynamic efficiency leads to sustainability of renewable resources but not the other way around. For the economic-ecological system as a whole, dynamic efficiency and intergenerational equity similarly lead to sustainability, but ad hoc rules of sustainability may well lead to sacrifices in human welfare. We then address the challenges of extending economic sustainability to space as well as time and discuss the factors leading to optimal islands of preservation regarding renewable resources. Exogenous mandates based on moral imperatives such as self-sufficiency and strong sustainability may result in missed win-win opportunities that could improve both the economy and the environment, as well as increase social welfare across generations.Islands of sustainability, sustainable development, sustainability science, fisheries, forests

Snow and ice melt flow features on Devon Island, Nunavut, Arctic Canada as possible analogs for recent slope flow features on Mars

Based on morphologic and contextual analogs from Devon Island, Arctic Canada, the recent martian slope flow features reported by Malin and Edgett are reinterpreted as being due not necessarily to groundwater seepage but possibly to snow or ice melt

Educating Negotiators for a Connected World: Volume 4 in the Rethinking Negotiation Teaching Series

In 2011 more than 60 of the world\u27s leading negotiation scholars gathered in Beijing for the Rethinking Negotiation Teaching project’s third and final international conference. The event, like the preceding conferences in Rome and Istanbul, was designed to inspire a diverse and energetic group of scholars to push forward their thinking on what is taught and how it is taught in contemporary negotiation courses. The resulting productivity required two volumes. This one wraps up the project as a whole. Multi-disciplinary and multi-national teams address the challenges of teaching negotiation in the face of profound cultural difference; move forward a project special focus on “wicked problems” (those ill-defined, ambiguous challenges for which even defining “the problem” is elusive, let alone attaining a “solution”); design innovative and concrete teaching tools for use both in and outside of the classroom; and introduce an array of new topics for the field, ranging from the possibilities of “informal” education to the role of physical movement in negotiation instruction.https://open.mitchellhamline.edu/dri_press/1003/thumbnail.jp

Backfilling Canals to Restore Wetlands: Empirical Results in Coastal Louisiana

Wetland restoration is largely a developing science and engineering enterprise. Analyses of results are too few and constrained to observations over a few years. We report here on the effectiveness of one restoration technique used sparsely in coastal Louisiana for several decades. Canals have been dredged in coastal Louisiana wetlands since 1938 for oil and gas exploration and extraction. These canals are typically dredged to 2.5 m depth and are 20 to 40 m wide. Canal lengths vary from 100 m to several 1000s m in the case of outer continental shelf pipeline canals that cross the wetlands. Today, thousands of miles of canals crisscross these wetlands. Studies have linked dredged canals to a number of undesirable effects on the wetland environment including alterations in salinity, flooding and drainage patterns, direct loss of marsh by convention to open water, and increases in marsh erosion rates. These effects have led state and federal agencies charged with managing the wetland resource to look for methods of mitigating canal impacts. One possible method of managing spoil banks after the abandonment of a drilling site is to return spoil material from the spoil banks to the canal with the hope that marsh vegetation will be reestablished on the old spoil banks and in the canal. The movement of former spoil bank material back into the canal is referred to as ‘backfilling’. The purpose of this study was to (1) examine how backfilled canals changed over 10 years, (2) examine factors influencing success with multiple regression statistical models, and, (3) compare costs of backfilling with other Louisiana marsh restoartion projects. We examined the sites to document and interpret changes occurring since 1983/4 and to statistically model the combined data derived from these new and previous analyses. Specifically, we wanted to determine the recovery rates of vegetation, water depth, and soils in backfilled canals, ‘restored’ spoil banks, and in nearby marshes, and to quantify the influence of plugging canals on these rates. The major factors determining backfilling restoration success are the depth of the canal, soil type, canal dimensions, locale, dredge operator skill, and permitting conditions. Plugging the canal has no apparent effect on water depth or vegetation cover, with the exception that submerged aquatic vegetation may be more frequently observed behind backfilled canals with plugs than in backfilled canals without plugs. Canal age, soil organic matter content, and whether restoration was done as mitigation on-site or off-site were the most important predictors of final canal depth. Canal length and percentage of spoil returned (+) had the greatest effect on the restoration of vegetation cover. Backfilled canals were shallower if they were older, in soils lower in organic matter, and backfilled off-site. Backfilling the canal restores wetlands at a cost of $1,200 to$3,400/ha, which compares very favorably with planned restoration projects in south Louisiana

Educating Negotiators for a Connected World: Volume 4 in the Rethinking Negotiation Teaching Series

In 2011 more than 60 of the world\u27s leading negotiation scholars gathered in Beijing for the Rethinking Negotiation Teaching project’s third and final international conference. The event, like the preceding conferences in Rome and Istanbul, was designed to inspire a diverse and energetic group of scholars to push forward their thinking on what is taught and how it is taught in contemporary negotiation courses. The resulting productivity required two volumes. This one wraps up the project as a whole. Multi-disciplinary and multi-national teams address the challenges of teaching negotiation in the face of profound cultural difference; move forward a project special focus on “wicked problems” (those ill-defined, ambiguous challenges for which even defining “the problem” is elusive, let alone attaining a “solution”); design innovative and concrete teaching tools for use both in and outside of the classroom; and introduce an array of new topics for the field, ranging from the possibilities of “informal” education to the role of physical movement in negotiation instruction.https://open.mitchellhamline.edu/dri_press/1003/thumbnail.jp