A simple, wide-range, linear thermistor-based temperature indicator

A novel thermistor-based temperature indicator using an RC oscillator and an up/down counter has been developed and described. The indicator provides linear performance over a wide dynamic temperature range of 0-100°C. This indicator is free from the error due to lead resistances of the thermistor and gives a maximum error of ±0 · 1°C in the range 0-100°C. Test results are given to support the theory.

Yksi historia monimutkaistuvasssa maailmassa : Historian olemus ja historian suuret kertomukset luokanopettajaopiskelijoiden historiatietoisuudessa

One history in a multicomplex world The quintessence of history and grand historical narratives in the historical consciousness of class teacher students The study analyses the conception of history amongst class teacher students at the University of Helsinki. It also explores the expectations about the future that the students have on the basis of their views on history. The conceptions of the students are analysed against the background of the notion of one history which has been part of Western thought in the modern era and which is at the centre of the theoretical framework of this study. The Enlightenment project and the erosion of the role of the Church paved the way for the notion that history is an linear narrative of the progress of humankind and in which, implicitly, the Western countries are endowed with a special role as the vanguards of progress. In recent times these assumptions have been criticised by postmodernists and proponents of New History. The material of the study consists of interviews of twenty-two 19 26 years old class teacher students at the University of Helsinki. The topics in the interviews were the developments of the past and the future trajectories. The students conceived history as a field of knowledge that provides a unifying view on the world and helps to make today s world intelligible. Finnish history and global history were invested with features of a grand narrative of progress. In global history, progress and development were seen as characteristic of the Western world primarily. The students regarded the post-war Finnish history as a qualified success story in that they deplored the erosion of collectivist values and the rise of selfishness in recent decades. History was not conceived as a process of progress that would self-evidently continue in the future, but rather more as a field of contingency and cyclical change.The students regarded the increasing predominance of the market forces over democratically elected agencies, the antagonism between the West and the other parts of the world, and environmental risks as the major threats. Notwithstanding this general.pessimism about the future, the students had a very positive view of their own personal prospects. Keywords: historical consciouness, one history, future expectations

Complete and interpretable conformance checking of business processes

This article presents a method for checking the conformance between an event log capturing the actual execution of a business process, and a model capturing its expected or normative execution. Given a business process model and an event log, the method returns a set of statements in natural language describing the behavior allowed by the process model but not observed in the log and vice versa. The method relies on a unified representation of process models and event logs based on a well-known model of concurrency, namely event structures. Specifically, the problem of conformance checking is approached by folding the input event log into an event structure, unfolding the process model into another event structure, and comparing the two event structures via an error-correcting synchronized product. Each behavioral difference detected in the synchronized product is then verbalized as a natural language statement. An empirical evaluation shows that the proposed method scales up to real-life datasets while producing more concise and higher-level difference descriptions than state-of-the-art conformance checking methods.

On a linear steady-state system of equations in microcontinuum fluid mechanics

Galerkin representations and integral representations are obtained for the linearized system of coupled differential equations governing steady incompressible flow of a micropolar fluid. The special case of 2-dimensional Stokes flows is then examined and further representation formulae as well as asymptotic expressions, are generated for both the microrotation and velocity vectors. With the aid of these formulae, the Stokes Paradox for micropolar fluids is established.

Simple software processes and tests improve the reliability and usefulness of a model.

Models are abstractions of reality that have predetermined limits (often not consciously thought through) on what problem domains the models can be used to explore. These limits are determined by the range of observed data used to construct and validate the model. However, it is important to remember that operating the model beyond these limits, one of the reasons for building the model in the first place, potentially brings unwanted behaviour and thus reduces the usefulness of the model. Our experience with the Agricultural Production Systems Simulator (APSIM), a farming systems model, has led us to adapt techniques from the disciplines of modelling and software development to create a model development process. This process is simple, easy to follow, and brings a much higher level of stability to the development effort, which then delivers a much more useful model. A major part of the process relies on having a range of detailed model tests (unit, simulation, sensibility, validation) that exercise a model at various levels (sub-model, model and simulation). To underline the usefulness of testing, we examine several case studies where simulated output can be compared with simple relationships. For example, output is compared with crop water use efficiency relationships gleaned from the literature to check that the model reproduces the expected function. Similarly, another case study attempts to reproduce generalised hydrological relationships found in the literature. This paper then describes a simple model development process (using version control, automated testing and differencing tools), that will enhance the reliability and usefulness of a model.

Equilibrium studies of ammonium exchange with Australian natural zeolites

This paper is concerned with the study of the equilibrium exchange of ammonium ions with two natural zeolite samples sourced in Australia from Castle Mountain Zeolites and Zeolite Australia. A range of sorption models including Langmuir Vageler, Competitive Langmuir, Freundlich, Temkin, Dubinin Astakhov and Brouers–Sotolongo were applied in order to gain an insight as to the exchange process. In contrast to most previous studies, non-linear regression was used in all instances to determine the best fit of the experimental data. Castle Mountain natural zeolite was found to exhibit higher ammonium capacity than Zeolite Australia material when in the freshly received state, and this behavior was related to the greater amount of sodium ions present relative to calcium ions on the zeolite exchange sites. The zeolite capacity for ammonium ions was also found to be dependent on the solution normality, with 35–60% increase inuptake noted when increasing the ammonium concentration from 250 to 1000 mg/L. The optimal fit ofthe equilibrium data was achieved by the Freundlich expression as confirmed by use of Akaikes Information Criteria. It was emphasized that the bottle-point method chosen influenced the isotherm profile in several ways, and could lead to misleading interpretation of experiments, especially if the constant zeolite mass approach was followed. Pre-treatment of natural zeolite with acid and subsequently sodium hydroxide promoted the uptake of ammonium species by at least 90%. This paper highlighted the factors which should be taken into account when investigating ammonium ion exchange with natural zeolites.

A linear root water uptake model

A model of root water extraction is proposed, in which a linear variation of extraction rate with depth is assumed. Five crops are chosen for simulation studies of the model, and soil moisture depletion under optimal conditions from different layers for each crop is calculated. Similar calculations are also made using the constant extraction rate model. Rooting depth is assumed to vary linearly with potential evapotranspiration for each crop during the vegetative phase. The calculated depletion patterns are compared with measured mean depletion patterns for each crop. It is shown that the constant extraction rate model results in large errors in the prediction of soil moisture depletion, while the proposed linear extraction rate model gives satisfactory results. Hypothetical depletion patterns predicted by the model in combination with a moisture tension-dependent sink term developed elsewhere are indicated.

Structural origin of set-reset processes in Ge15Te83Si2 glass investigated using in situ Raman scattering and transmission electron microscopy

We report here that the structural origin of an easily reversible Ge15Te83Si2 glass can be a promising candidate for phase change random access memories. In situ Raman scattering studies on Ge15Te83Si2 sample, undertaken during the amorphous set and reset processes, indicate that the degree of disorder in the glass is reduced from off to set state. It is also found that the local structure of the sample under reset condition is similar to that in the amorphous off state. Electron microscopic studies on switched samples indicate the formation of nanometric sized particles of c-SiTe2 structure. ©2009 American Institute of Physics

Mast cells and endothelial erosion: Implications for human atherothrombotic disease

More than 40% of all deaths in Finland are caused by atherosclerosis. The complications of atherosclerosis are due to either detachment of the luminal endothelium (erosion) or rupture of the fibrous cap of an atherosclerotic plaque (rupture). As a result, a thrombus is formed at the site of the intimal lesion. Indeed, erosions cause roughly 40% of sudden atherothrombotic deaths and 25% of all atherothrombotic deaths. Erosions are overrepresented in young subjects, diabetics, smokers and women. This dissertation focuses on endothelial erosion. Endothelial erosions were studied in the context of arterial grafting and vascular inflammation. Special attention was given to the role of intimal mast cells and the methodological viewpoints of reliable identification of endothelial erosions. Mast cells are inflammatory cells mostly known for their ability to cause allergic symptoms. In addition to occurring in skin and mucosal surfaces, mast cells are abundant in arterial intima and adventitia. In this study, mast cells were found to associate with endothelial erosions in non-lesional and atherosclerotic human coronary arteries. Thus, mast cells may participate in atherogenesis at the initial phases of the disease process already. We also showed that the mast cell proteases tryptase, chymase, and cathepsin G are all capable of cleaving molecules essential for endothelial cell-to-cell and cell-to-extracellular matrix interactions, such as VE-cadherin and fibronectin. Symptom-causing carotid plaques were found to contain more inflammatory cells, especially mast cells, than non-symptom-causing plaques. Furthermore, the atherogenic serum lipid profile and the degree of carotid stenosis turned out to correlate with the density of carotid plaque mast cells. Apoptotic and proliferating cells were more abundant in non-symptom causing plaques (active renewal of endothelial cells), but erosions were larger in symptom-causing plaques (capacity of endothelial regeneration exceeded). The process of identifying endothelial erosions with immunostainings has been ambiguous, since both endothelial cells and platelets express largely the same antigens. This may have caused inaccurate interpretations of the presence of endothelial erosion. In the last substudy of this thesis we developed a double immunostaining method for simultaneous identification of endothelial cells and platelets. This method enables more reliable identification of endothelial erosions.

CSSI-PRO: a method for secondary structure type editing, assignment and estimation in proteins using linear combination of backbone chemical shifts

Estimation of secondary structure in polypeptides is important for studying their structure, folding and dynamics. In NMR spectroscopy, such information is generally obtained after sequence specific resonance assignments are completed. We present here a new methodology for assignment of secondary structure type to spin systems in proteins directly from NMR spectra, without prior knowledge of resonance assignments. The methodology, named Combination of Shifts for Secondary Structure Identification in Proteins (CSSI-PRO), involves detection of specific linear combination of backbone H-1(alpha) and C-13' chemical shifts in a two-dimensional (2D) NMR experiment based on G-matrix Fourier transform (GFT) NMR spectroscopy. Such linear combinations of shifts facilitate editing of residues belonging to alpha-helical/beta-strand regions into distinct spectral regions nearly independent of the amino acid type, thereby allowing the estimation of overall secondary structure content of the protein. Comparison of the predicted secondary structure content with those estimated based on their respective 3D structures and/or the method of Chemical Shift Index for 237 proteins gives a correlation of more than 90% and an overall rmsd of 7.0%, which is comparable to other biophysical techniques used for structural characterization of proteins. Taken together, this methodology has a wide range of applications in NMR spectroscopy such as rapid protein structure determination, monitoring conformational changes in protein-folding/ligand-binding studies and automated resonance assignment.

A conditionally linearized Monte Carlo filter in non-linear structural dynamics

State and parameter estimations of non-linear dynamical systems, based on incomplete and noisy measurements, are considered using Monte Carlo simulations. Given the measurements. the proposed method obtains the marginalized posterior distribution of an appropriately chosen (ideally small) subset of the state vector using a particle filter. Samples (particles) of the marginalized states are then used to construct a family of conditionally linearized system of equations and thus obtain the posterior distribution of the states using a bank of Kalman filters. Discrete process equations for the marginalized states are derived through truncated Ito-Taylor expansions. Increased analyticity and reduced dispersion of weights computed over a smaller sample space of marginalized states are the key features of the filter that help achieve smaller sample variance of the estimates. Numerical illustrations are provided for state/parameter estimations of a Duffing oscillator and a 3-DOF non-linear oscillator. Performance of the filter in parameter estimation is also assessed using measurements obtained through experiments on simple models in the laboratory. Despite an added computational cost, the results verify that the proposed filter generally produces estimates with lower sample variance over the standard sequential importance sampling (SIS) filter.

TU10025 Erosion control - turf research and development facility

The aim of this project is to construct a large-scale erosion control education and demonstration facility at Redland Research Station. This will be done in collaboration with the Australian turf industry (as members of the steering committee) and consultant researcher Dr Rob Loch (project partner). The project will employ a part-time industry development officer (IDO) for Turf Australia to increase engagement with the project by the target audience. The project’s main strategy is to extend the research results from HAL funded project Optimising Turf Use to Minimise Soil Erosion on Construction Sites TU08033 so that the maximum return on investment can be derived for the turf levy payers and HAL from that study.

Non-linear flapping vibrations of rotating blades

The non-linear equations of motion of a rotating blade undergoing extensional and flapwise bending vibration are derived, including non-linearities up to O (ε3). The strain-displacement relationship derived is compared with expressions derived by earlier investigators and the errors and the approximations made in some of those are brought out. The equations of motion are solved under the inextensionality condition to obtain the influence of the amplitude on the fundamental flapwise natural frequency of the rotating blade. It is found that large finite amplitudes have a softening effect on the flapwise frequency and that this influence becomes stronger at higher speeds of rotation.

Use of transverse polarization to probe R-parity violating supersymmetry at ILC

In supersymmetric theories with R-parity violation, squarks and sleptons can mediate Standard Model fermion–fermion scattering processes. These scalar exchanges in e+e− initiated reactions can give new signals at future linear colliders. We explore use of transverse beam polarization in the study of these signals in the process View the MathML source. We highlight certain asymmetries, which can be constructed due to the existence of the transverse beam polarization, which offer discrimination from the Standard Model (SM) background and provide increased sensitivity to the R-parity violating couplings.