Rapid Frequency Estimation

Frequency estimation plays an important role in many digital signal processing applications. Many areas have benefited from the discovery of the Fast Fourier Transform (FFT) decades ago and from the relatively recent advances in modern spectral estimation techniques within the last few decades. As processor and programmable logic technologies advance, unconventional methods for rapid frequency estimation in white Gaussian noise should be considered for real time applications. In this thesis, a practical hardware implementation that combines two known frequency estimation techniques is presented, implemented, and characterized. The combined implementation, using the well known FFT and a less well known modern spectral analysis method known as the Direct State Space (DSS) algorithm, is used to demonstrate and promote application of modern spectral methods in various real time applications, including Electronic Counter Measure (ECM) techniques

Low-complexity high prediction accuracy visual quality metrics and their applications in H.264/AVC encoding mode decision process

In this thesis, we develop a new general framework for computing full reference image quality scores in the discrete wavelet domain using the Haar wavelet. The proposed framework presents an excellent tradeoff between accuracy and complexity. In our framework, quality metrics are categorized as either map-based, which generate a quality (distortion) map to be pooled for the final score, e.g., structural similarity (SSIM), or non map-based, which only give a final score, e.g., Peak signal-to-noise ratio (PSNR). For mapbased metrics, the proposed framework defines a contrast map in the wavelet domain for pooling the quality maps. We also derive a formula to enable the framework to automatically calculate the appropriate level of wavelet decomposition for error-based metrics at a desired viewing distance. To consider the effect of very fine image details in quality assessment, the proposed method defines a multi-level edge map for each image, which comprises only the most informative image subbands. To clarify the application of the framework in computing quality scores, we give some examples showing how the framework can be applied to improve well-known metrics such as SSIM, visual information fidelity (VIF), PSNR, and absolute difference. We compare the complexity of various algorithms obtained by the framework to the Intel IPP-based H.264 baseline profile encoding using C/C++ implementations. We evaluate the overall performance of the proposed metrics, including their prediction accuracy, on two well-known image quality databases and one video quality database. All the simulation results confirm the efficiency of the proposed framework and quality assessment metrics in improving the prediction accuracy and also reduction of the computational complexity. For example, by using the framework, we can compute the VIF at about 5% of the complexity of its original version, but with higher accuracy. In the next step, we study how H.264 coding mode decision can benefit from our developed metrics. We integrate the proposed SSEA metric as the distortion measure inside the H.264 mode decision process. The H.264/AVC JM reference software is used as the implementation and verification platform. We propose a search algorithm to determine the Lagrange multiplier value for each quantization parameter (QP). The search is applied on three different types of video sequences having various motion activity features, and the resulting Lagrange multiplier values are tabulated for each of them. Based on our proposed Framework we propose a new quality metric PSNRA, and use it in this part (mode decision). The simulated rate-distortion (RD) curves show that at the same PSNRA, with the SSEA-based mode decision, the bitrate is reduced about 5% on average compared to the conventional SSE-based approach for the sequences with low and medium motion activities. It is notable that the computational complexity is not increased at all by using the proposed SSEA-based approach instead of the conventional SSE-based method. Therefore, the proposed mode decision algorithm can be used in real-time video coding

National Educators' Workshop: Update 95. Standard Experiments in Engineering Materials Science and Technology

This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 95. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community

Two case studies exploring opportunities and constraints for soil organic carbon sequestration following land use change

The flux of carbon (C) between the terrestrial biosphere and the atmosphere occurs naturally as part of the carbon cycle (CC). However, anthropogenic activity can disrupt the natural equilibrium of the CC. Although fossil fuel burning is the largest cause of human induced C emissions to the atmosphere, land use and land use change (LULUC) also results in emissions. Of particular concern is soil disturbance and erosion caused by LULUC activities including deforestation, tillage and overgrazing. These activities can lead to a net loss of C from the terrestrial biosphere leading to increased levels of greenhouse gas in the atmosphere. This outcome is a major factor widely understood to adversely affect the rate of global warming, climate change and extreme weather events. There has been a great deal of research undertaken to show that LULUC activities can also lead to the sequestration and long term storage of C in soil. LULUC practices that result in increases in soil organic matter (SOM), humification and aggregation improve soil quality, water quality, enhance food security and increase biodiversity. The activities also result in the sequestration of atmospheric CO2 as soil organic carbon (SOC) and therefore may contribute to the reduction or stabilisation of atmospheric CO2 levels and mitigate the adverse effects of climate change. This thesis describes the effects of two different LULUC activities on the C sequestration potential of soil. In this research two case studies have been used to explore three principal aims. Firstly to identify the C sequestration potential of agricultural soil following LUC; then to determine whether there is a steady rate of SOC sequestration over time following LUC, and finally to identify biogeochemical factors that contribute to the C sequestration potential of soil after LUC. The first case study was undertaken on the Southern Tablelands of New South Wales (NSW), a temperate region with approximately 670 mm mean average rainfall (MAR). The study involved comparing the soil C stock (SCS) to 30 cm depth, in agricultural land (AL) principally used for grazing, with the SCS from 20 biodiverse environmental plantings (BEP) established between one and 19 years prior to sampling. BEPs, otherwise referred to as mixed species environmental plantings (MSEP), windbreaks or shelterbelts, can be established using either a direct seeding method or from tube-stock. The sites included in this study were all directly seeded in either linear or block configurations using a mix of native eucalypt and acacia trees and understory shrubs. At each site three paired 10 m transects were established on a tree line (TL), the inter-row (IR) and in the adjacent AL. The AGB was determined for each TL transect. Three soil cores to 30 cm depth were taken from each transect and separated into 0-5, 5-10, 10-20 and 20-30 cm increments. The soil samples were analysed for SOC, total nitrogen (TN), total phosphorus (TP), and by using mid infrared spectroscopy (MIRS) analysis soil fraction changes were also determined. The measured AGB and SCS results were compared with FullCAM modelled data. The overall aim of this case study was to determine whether BEPs sown into AL led to SOC sequestration, and whether the rate of increase could be predicted based on tree age and biomass. The results of the BEP case study show that the average soil CS in the AL based on an equivalent soil mass (ESM) was 41.1 Mg C ha-1 (41.1 tonnes C ha-1). BEPs aged 11-15 years had the highest SCS of 49.3 Mg C ha-1. The oldest BEP sites aged between 16 and 19 years had a lower SCS of 45.7 Mg C ha-1. Overall, the average SCS rate of increase was 0.5 Mg C ha-1 yr-1. However, the results show significant variation between sites and no trend suggesting there is a temporal increase in SCS. The average AGB for all sites was found to be 31.4 Mg C ha-1 with the range between 0.2 Mg C ha-1 in a two year old site, and 97.0 Mg C ha-1 in a site aged 16 years. The average annual rate of AGB change was found to be 2.4 Mg C ha-1 yr-1. The results show there is no relationship between AGB and SCS. Therefore the prediction of changes to SCS based on AGB increase alone is not possible. The results also show that site factors and nutrient availability have an influence on the SOC sequestration potential of the BEPs and the sustainability of the SCS. The second case study was undertaken in the semi-arid rangelands of the Central West of NSW. The MAR of the region is approximately 440 mm. The study examined whether waterponding, an effective environmental restoration activity used to rehabilitate scalded soil, would result in increases in SCS. The research involved comparing the SCS of three scalded sites with 12 waterpond sites established between 1 and 27 years prior to sampling. Nine soil cores to 30 cm depth were taken at each scald site. Three waterponds were sampled at each of the 12 waterpond sites. Nine soil cores to 30 cm depth were taken from three positions (wall, mid and top) within in each waterpond. Each soil core was separated into 0-5, 5-10, 10-20 and 20-30 cm increments. Every sample was analysed for pH, electrical conductivity (EC), SOC, TN, and total C. The results show that waterponds have a significantly lower EC than scalded soil. This change occurs because soluble salts are leached from the saline scald soil profile after waterponding. The results also show that the scalded soil has an average SCS to 30cm depth of 18.7 Mg C ha-1. Waterponds aged five years had a SCS of 26.1 Mg C ha-1. This represents a rate of increase of 1.5 Mg C ha-1yr-1. The 10 year old and 25-27 year old waterponds have a slightly lower SCS of 25.3 and 24.9 Mg C ha-1. The probable reason for the apparent decline in SCS in the older water ponds is associated with the lower bulk density found in these older waterponds and the increased presence of SOM. A number of edaphic factors were found to influence the potential of the scalds to sequester SOC. To make such assessments within research resource constraints three different subsets of the soil samples were compiled. Initially, a sub-set of 144 samples including one scald, and waterponds aged 1 year, 5 years and 25 years since establishment were analysed for aggregate stability, TP, total sulfur (TS), and available P (AP). The results from this subset were used to identify temporal changes to soil stability and to ascertain whether these soil nutrient concentrations were affected by waterponding or influenced the SOC sequestration potential of the soils. The aggregate stability results show there is a temporal change in the dispersability of the soils following waterponding. Scalded soils are stable because of the high concentration of soluble salts. After the salts are leached from the profile the soils become more susceptible to dispersion. The results also indicate that total N, P and S is not limiting, but AP is limiting ongoing sequestration of C in the waterponds. A smaller subset of samples made up of one scald core and a paired 27 year old waterpond core were analysed for cation exchange capacity, x-ray diffraction and x-ray fluorescence to identify any mineralogical differences that may be attributable to waterponding. Calcite was found to be leached from the scald profile, hematite increased due to iron oxide formation, gypsum, kaolinite, illite and vermiculite was higher in the waterponded soil than the scalded soil whereas smectite was lower in the waterponds. These differences are most likely due to weathering processes and aeolian deposition. Across the scalded soil surface there are occasional hummocks of vegetation. Cesium-137 analysis was undertaken to determine whether the hummocks were recent deposits or relics of the original soil profile. For this analysis composite samples were made up from the three scald sites, two hummock sites and waterponds aged between 25 and 27 years since establishment. The results from this small study indicate the hummocks are most likely to be recent deposits of aeolian material. The experimental results from this project show that LULUC can lead to an increase in SCS. The higher SCS found in the BEPs may not be sustainable because the oldest sites show a lower SCS than the younger sites. The results suggest reasons for the decline are most likely due to site factors and lower levels of nutrient availability. The SCS sequestered in the scalded soil rehabilitated by waterponding however, is likely to have been sequestered permanently so long as the rehabilitated landscape is managed sustainably

Fundamentals

Volume 1 establishes the foundations of this new field. It goes through all the steps from data collection, their summary and clustering, to different aspects of resource-aware learning, i.e., hardware, memory, energy, and communication awareness. Machine learning methods are inspected with respect to resource requirements and how to enhance scalability on diverse computing architectures ranging from embedded systems to large computing clusters

Fundamentals

Volume 1 establishes the foundations of this new field. It goes through all the steps from data collection, their summary and clustering, to different aspects of resource-aware learning, i.e., hardware, memory, energy, and communication awareness. Machine learning methods are inspected with respect to resource requirements and how to enhance scalability on diverse computing architectures ranging from embedded systems to large computing clusters

Instrumental and chemometric methodologies to assess sensory quality of Mediterranean food

L'oli d'oliva, el vi o els fruits secs són productes típics de la regió Mediterrània que ofereixen un valor afegit gràcies als seus beneficis per a la salut i excel·lents característiques sensorials. Per aquest motiu és necessari un control de la qualitat i autenticitat d'aquests productes, que són altament susceptibles a fraus i adulteracions. Un aspecte important és l'avaluació de la qualitat sensorial, que descriu paràmetres percebuts pels sentits (gust, visió, olor i tacte) mitjançant panells validats i entrenats d'experts. Aquests panells tendeixen a ser subjectius i requereixen llargs temps d'anàlisi i alts costos. Com a conseqüència hi ha hagut un increment en el desenvolupament de tècniques d'anàlisi capaces de simular les respostes obtingudes amb el panell de tast humà. L'anomenat 'panell electrònic' ofereix respostes objectives mitjançant l'ús de tècniques multivariants que permeten establir correlacions entre els descriptors definits pels humans i els senyals obtingudes instrumentalment. Aquesta tesi pretén oferir tècniques instrumentals alternatives, ràpides i senzilles per determinar la qualitat sensorial d'aliments com l'oli d'oliva, el vi o les ametlles. Els estudis duts a terme inclouen el tractament de les respostes sensorials obtingudes mitjançant metodologies de referència (principalment panells de tast humans), l'optimització dels procediments analítics per treballar amb tècniques instrumentals i el desenvolupament d'eines quimiomètriques adequades per construir els models multivariants. També s'han desenvolupat estratègies de fusió de dades per combinar les diferents dades instrumentals que simulen els sentits humans (olor, gust i visió).El aceite de oliva, el vino o los frutos secos son productos típicos de la región Mediterránea que ofrecen un valor añadido gracias a sus beneficios para la salud y excelentes características sensoriales. Por este motivo es necesario un control de la calidad y autenticidad de estos productos, que son altamente susceptibles a fraudes y adulteraciones. Un aspecto importante es la evaluación de la calidad sensorial, que describe parámetros percibidos por los sentidos (gusto, visión, olor y tacto) mediante paneles validados y entrenados de expertos. Estos paneles tienden a ser subjetivos, requieren largos tiempos de análisis y altos costes. Como consecuencia ha habido un incremento en el desarrollo de técnicas de análisis capaces de simular las respuestas obtenidas con el panel de cata humano. El llamado 'panel electrónico' ofrece respuestas objetivas mediante el uso de técnicas multivariantes que permiten establecer correlaciones entre los descriptores definidos por los humanos y las señales obtenidas instrumentalmente. Esta tesis pretende ofrecer técnicas instrumentales alternativas, rápidas y sencillas para determinar la calidad sensorial de alimentos como el aceite de oliva, el vino o las almendras. Los estudios llevados a cabo incluyen el tratamiento de las respuestas sensoriales obtenidas mediante metodologías de referencia (principalmente paneles de cata humanos), la optimización de los procedimientos analíticos para trabajar con técnicas instrumentales y el desarrollo de herramientas quimiométricas adecuadas para construir los modelos multivariantes. También se han desarrollado estrategias de fusión de datos para combinar los diferentes datos instrumentales que simulan los sentidos humanos (olor, gusto y visión).Olive oil, wine or nuts are typical products of the Mediterranean region that offer added value thanks to its health benefits and excellent sensory characteristics. Therefore, the control the quality and authenticity of these products is necessary, mainly because they are highly susceptible to fraud and adulterations. An important aspect is the evaluation of sensory quality that describe parameters perceived by the senses (taste, sight, smell and touch) using validated and trained panels of experts. These panels tend to be subjective, requiring long-time analysis and high costs. As a result there has been an increase in the development of analytical techniques capable to simulate the responses obtained with the human taste panel. The so-called 'electronic panel' provides objective responses using multivariate techniques, which establish correlations between descriptors defined by humans and signals obtained instrumentally. This thesis aims to offer fast and simple alternative instrumental techniques to determine the sensory quality of foods such as olive oil, wine and almonds. Studies carried out include the treatment of sensory responses obtained by reference methodologies (mainly human taste panels), optimization of analytical procedures to work with instrumental techniques and the development of appropriate chemometric tools to build multivariate models. Data fusion strategies have also been studied by combining different instrumental data that simulate the human senses (smell, taste and sight)

The assembly and structure of self-assembling peptides: molecular to supramolecular

Self-assembling molecules are central to a plethora of processes found in nature, biotechnology and even disease. The importance of the non-covalent interaction of monomers to the formation of fibrillar assemblies is evident in the repeated use of this mechanism throughout nature, from essential cellular processes such as the formation of the cytoskeleton to the production of silk. Further, it has been recognised in the last two decades that a self-assembly mechanism, that is the formation of amyloid, underpins the pathology of protein misfolding diseases; it is therefore essential to dissect these mechanisms. Despite recent technological and model system developments, self-assembling molecules remain challenging to investigate. Using combined structural and biophysical characterisations of penta- and hexa-peptide self-assembling model systems these investigations shed further light on the structure of amyloid-like fibrils. The elucidation of the structures of these fibrillar systems not only has implications for disease but also makes them well placed for consideration for biotechnological applications. In reflecting upon how cross-ß structural architectures can be organised in the fibrillar state, a molecular and supramolecular model of fibrils formed by a fragment of !-synuclein is reported. The fibrils are found to consist of a novel and elaborate cross-ß architecture that leads to a helical supramolecular assembly spanning length scales previously unobserved for such a system. Where self-assembly is a useful route to supramolecular structure formation, the use of low molecular weight gelator (LMWG) peptides to create fibrillar structures with defined material properties is also explored. The complex link between molecular structure, self-assembled architecture, fibril formation, fibril interaction and ultimately bulk material properties is described. It is found that the determinants of self-assembly are distinct from the determinants of gelation and so future LMWG design will have to consider both individually. This work presents methodological advances in the characterisation of self-assembled structures. The investigations presented here have relevance for disease related processes but also to the technological use of these systems as materials. Finally, this work emphasises the beauty of the extravagant, yet elegant connection between molecular interaction and supramolecular selfassembly

Quantification of Mitochondrial Zinc Homeostasis and Analysis of Zinc and Polyamine-Mediated Axonal Trafficking

The zinc ion is an important emerging signaling molecule for biological processes. In this work we engineered improved zinc sensors based on our previously developed fluorescent sensor GZnP1 to provide sensors with a higher fluorescent readout, faster kinetics, and a superior sensitivity to zinc. We utilized these zinc sensors and further developed the sensors to answer questions pertaining to biological zinc. We showed the labile zinc concentration in the mitochondrial matrix was less than 1 pM while the labile zinc concentration in the cytosol and mitochondrial IMS were comparable (~100 pM) across four different cell lines. Using these zinc sensors we found that exposure to high labile zinc only overloaded the cytosol and the mitochondrial IMS with zinc while the mitochondrial matrix did not sequester excess labile zinc. We highlighted the importance of mitochondrial labile zinc dynamics and concentrations across different mitochondrial locations and distinguished the mitochondria as not being a storage site for zinc. In this work we revealed, for the first time, a novel vital role zinc plays in the regulation of cellular trafficking. High load of zinc can arrest the motility of mitochondria, lysosomes and vesicles in both HeLa cells and neurons. The zinc-microtubule interaction was found to prevent motor proteins from landing on microtubules obstructing microtubule-based motility. Zinc was identified as interacting with two histidine residues on the α-tubulin monomer of microtubules. This finding resolved the long lasting controversy regarding the signaling roles of labile zinc and provided solid, direct and strong evidence confirming that zinc act as a significant intracellular signaling molecule. In addition to zinc, polyamines were investigated as a potential specific regulator of mitochondrial microtubule-based trafficking. We found a correlation between mitochondrial microtubule-based trafficking and abnormal polyamine concentrations resulting from Alzheimer’s disease (AD) in a Down syndrome (DS) cell model. Decreased mitochondrial motility was found in primary cultured rat hippocampal neurons as well as in the DS mouse hippocampal neuron model with increased polyamines. Polyamine production can be blocked using difuoromethylornithine (DFMO) a drug that inhibits ornithine decarboxylase (ODC) preventing the production of polyamines. DFMO restored mitochondrial motility in the DS mouse model. Mitochondrial motility in relation to polyamines has never been connected prior to these results indicating a novel pathway for the pathology of AD in DS brains. Two new regulatory mechanisms for axonal motility and exposure of previously unknown zinc mitochondrial relationships were discovered which has magnified our understanding of how the cell functions