Review of End-of-life Options for Structural Timber Buildings in New Zealand and Australia.

Deconstruction, at the end of the useful life of a building, produces a considerable amount of materials which must be disposed of, or be recycled / reused. At present, in New Zealand, most timber construction and demolition (C&D) material, particularly treated timber, is simply waste and is placed in landfills. For both technical and economic reasons (and despite the increasing cost of landfills), this position is unlikely to change in the next 10 – 15 years unless legislation dictates otherwise. Careful deconstruction, as opposed to demolition, can provide some timber materials which can be immediately re-used (eg. doors and windows), or further processed into other components (eg. beams or walls) or recycled (‘cascaded’) into other timber or composite products (e.g. fibre-board). This reusing / recycling of materials is being driven slowly in NZ by legislation, the ‘greening’ of the construction industry and public pressure. However, the recovery of useful material can be expensive and uneconomic (as opposed to land-filling). In NZ, there are few facilities which are able to sort and separate timber materials from other waste, although the soon-to-be commissioned Burwood Resource Recovery Park in Christchurch will attempt to deal with significant quantities of demolition waste from the recent earthquakes. The success (or otherwise) of this operation should provide good information as to how future C&D waste will be managed in NZ. In NZ, there are only a few, small scale facilities which are able to burn waste wood for energy recovery (e.g. timber mills), and none are known to be able to handle large quantities of treated timber. Such facilities, with constantly improving technology, are being commissioned in Europe (often with Government subsidies) and this indicates that similar bio-energy (co)generation will be established in NZ in the future. However, at present, the NZ Government provides little assistance to the bio-energy industry and the emergence worldwide of shale-gas reserves is likely to push the economic viability of bio-energy further into the future. The behaviour of timber materials placed in landfills is complex and poorly understood. Degrading timber in landfills has the potential to generate methane, a potent greenhouse gas, which can escape to the atmosphere and cancel out the significant benefits of carbon sequestration during tree growth. Improving security of landfills and more effective and efficient collection and utilisation of methane from landfills in NZ will significantly reduce the potential for leakage of methane to the atmosphere, acting as an offset to the continuing use of underground fossil fuels. Life cycle assessment (LCA), an increasingly important methodology for quantifying the environmental impacts of building materials (particularly energy, and global warming potential (GWP)), will soon be incorporated into the NZ Green Building Council Greenstar rating tools. Such LCA studies must provide a level playing field for all building materials and consider the whole life cycle. Whilst the end-of-life treatment of timber by LCA may establish a present-day base scenario, any analysis must also present a realistic end-of-life scenario for the future deconstruction of any 6 new building, as any building built today will be deconstructed many years in the future, when very different technologies will be available to deal with construction waste. At present, LCA practitioners in NZ and Australia place much value on a single research document on the degradation of timber in landfills (Ximenes et al., 2008). This leads to an end-of-life base scenario for timber which many in the industry consider to be an overestimation of the potential negative effects of methane generation. In Europe, the base scenario for wood disposal is cascading timber products and then burning for energy recovery, which normally significantly reduces any negative effects of the end-of-life for timber. LCA studies in NZ should always provide a sensitivity analysis for the end-of-life of timber and strongly and confidently argue that alternative future scenarios are realistic disposal options for buildings deconstructed in the future. Data-sets for environmental impacts (such as GWP) of building materials in NZ are limited and based on few research studies. The compilation of comprehensive data-sets with country-specific information for all building materials is considered a priority, preferably accounting for end-of-life options. The NZ timber industry should continue to ‘champion’ the environmental credentials of timber, over and above those of the other major building materials (concrete and steel). End-of-life should not be considered the ‘Achilles heel’ of the timber story

Invisible Pixels Are Dead, Long Live Invisible Pixels!

Privacy has deteriorated in the world wide web ever since the 1990s. The tracking of browsing habits by different third-parties has been at the center of this deterioration. Web cookies and so-called web beacons have been the classical ways to implement third-party tracking. Due to the introduction of more sophisticated technical tracking solutions and other fundamental transformations, the use of classical image-based web beacons might be expected to have lost their appeal. According to a sample of over thirty thousand images collected from popular websites, this paper shows that such an assumption is a fallacy: classical 1 x 1 images are still commonly used for third-party tracking in the contemporary world wide web. While it seems that ad-blockers are unable to fully block these classical image-based tracking beacons, the paper further demonstrates that even limited information can be used to accurately classify the third-party 1 x 1 images from other images. An average classification accuracy of 0.956 is reached in the empirical experiment. With these results the paper contributes to the ongoing attempts to better understand the lack of privacy in the world wide web, and the means by which the situation might be eventually improved.Comment: Forthcoming in the 17th Workshop on Privacy in the Electronic Society (WPES 2018), Toronto, AC

"It feels like I'm managing myself": HIV+ people tracking their personal health information

Nearly 37 million people live with HIV globally and recent advances in medicine have transformed HIV to a chronic disease, if managed. Previous research in Personal Health Informatics has investigated how people self-manage other chronic conditions, such as diabetes, by tracking and reflecting on their health information but there is little knowledge of how people do so for complex and socially stigmatized diseases like HIV. A better understanding of their specialized needs could lead to the development of more appropriate tools to self-manage their condition. Our paper introduces an iterative process model of Personal Health Informatics. We then describe the results of an empirical study involving HIV+ adults aimed at understanding their issues, concerns and actions in each of the stages of this process model. We provide implications for the design of personal informatics tools and open research directions that can lead to better self-management for people living with HIV

Mobilité de sexe et réussite scolaire au collégial

Cet article porte sur la vérification de certaines hypothèses relatives au lien entre sexe, identité de genre et réussite scolaire au collégial. Les chercheurs ont fait passer à tous les nouveaux inscrits au cégep d'Alma le questionnaire de BEM validé par Pelletier pour le Québec. Les résultats, exception faite de ce qui concerne les androgynes, semblent confirmer les hypothèses: ils indiquent que c'est le sexe plus que l'identité de genre qui influence la réussite scolaire au collégial et ce sont les étudiantes qui connaissent une véritable « mobilité de sexe » qui réussissent le mieux. Plus qu'une simple prise de distance du message social (transcendance des rôles sociaux de sexe), cette mobilité se traduit par une transgression de ce message social.This article examines various hypotheses describing the relationship between sex, gender identification and success at college. The authors administered the BEM questionnaire, validated in Quebec by Pelletier, to all newly enrolled students at Cegep Alma. The results show that except for androgynes, the hypotheses are confirmed: that sex more than gender identity influences success at college level; and that students who have "sexual mobility" have the highest success rate. This mobility seems to be manifested by a transgression of a social message which is more than a simple removal from this message ("transcendance of social sex roles").Este articulo estudia la verificacion de ciertas hipotesis sobre la relacion entre el sexo, la identidad del género y el éxito académico a nivel preuniversitario. Los investigadores aplicaron el cuestionario BEM, validado para el Québec por Pelletier, a todos los nuevos alumnos del colegio de Aima (Québec). Los resultados parecen confirmar que el sexo, mas que la identidad del género, tiene una influencia sobre el éxito académico a nivel preuniversitario excepto para androginos; y que los estudiantes con una verdadera "movilidad de sexo" obtienen un éxito mayor. Mas que un simple distanciamiento del mensaje social (la transcen-dencia de los papeles sociales del sexo), dicha movilidad se traduce en una transgresion de este mensaje social.Dieser Artikel behandelt die Verifikation gewisser Hypothesen beziiglich der Beziehung zwischen Geschlecht, sexueller Identitàt und Leistung auf dem College. Die Forscher haben aile neue Schiller des College von Alma den von Bern eingefuhrten und von Pelletier fur Quebec validierten Fragebogen ausftillen lassen. Abgesehen von den Zwittern scheinen die Ergebnisse die Hypothesen zu bestâtigen: der Erfolg im College hângt mehr vom Geschlecht ab als von der sexuellen Identitàt; aufierdem haben die Schiilerinnen mit richtiger "geschlechtsbezogener Mobilitât" den grôssten Erfolg. Uber eine einfache Abstandnahme gegeniiber der sozialen Regel (Transzendenz der geschlechtsbezogenen sozialen Rollen-verteilung) hinausgehend wird dièse Mobilitât zu einer Ubertretung dieser sozialen Regel

Feasibility and Detailing of Post-tensioned Timber Buildings for Seismic Areas

Paper 53This paper describes the structural design and selection of construction detailing for low-rise multi-storey timber buildings using a new and exciting structural timber system. This system, originally developed for use with pre-cast concrete, combines the use of un-bonded post-tensioning techniques and additional sources of energy dissipation. This system eliminates residual displacement, while greatly reducing the damage to structural members during a significant seismic event. The paper shows how this new structural system can be used with large size structural timber members manufactured from laminated veneer lumber (LVL) or glulam timber, for use in multistorey buildings, with lateral load resistance provided by post-tensioned structural timber frames or walls, separately or in combination. An extensive on-going research program at the University of Canterbury, New Zealand has tested a wide range of beam-to-column, wall-to-foundation and column-to-foundation connections under simulated seismic loading, all giving excellent results. As part of this contribution, a case study of the design methods, construction options, cost and feasibility of a six storey timber office building in a moderate seismic area is carried out. The structural design of this building allowed investigation of different methods of structural analysis, and the development of many construction and connection details offering feasibility of rapid construction. Total building cost was evaluated and compared to equivalent steel and reinforced concrete options

UCLA Space-Time Area Law Model: A Persuasive Foundation for Hadronization

From the studies of rates and distributions of heavy quark mesons we have developed additional evidence that hadron formation is dominantly controlled by a Space-Time Area Law, an approach suggested by both non-perturbative QCD and Relativistic String Models.Comment: 37 pages, 12 figures, 2 tables, Accepted for publication in Eur. Phys. J.

Synchronization reveals topological scales in complex networks

We study the relationship between topological scales and dynamic time scales in complex networks. The analysis is based on the full dynamics towards synchronization of a system of coupled oscillators. In the synchronization process, modular structures corresponding to well defined communities of nodes emerge in different time scales, ordered in a hierarchical way. The analysis also provides a useful connection between synchronization dynamics, complex networks topology and spectral graph analysis.Comment: 4 pages, 3 figure

Magnetic Vortex Resonance in Patterned Ferromagnetic Dots

We report a high-resolution experimental detection of the resonant behavior of magnetic vortices confined in small disk-shaped ferromagnetic dots. The samples are magnetically soft Fe-Ni disks of diameter 1.1 and 2.2 um, and thickness 20 and 40 nm patterned via electron beam lithography onto microwave co-planar waveguides. The vortex excitation spectra were probed by a vector network analyzer operating in reflection mode, which records the derivative of the real and the imaginary impedance as a function of frequency. The spectra show well-defined resonance peaks in magnetic fields smaller than the characteristic vortex annihilation field. Resonances at 162 and 272 MHz were detected for 2.2 and 1.1 um disks with thickness 40 nm, respectively. A resonance peak at 83 MHz was detected for 20-nm thick, 2-um diameter disks. The resonance frequencies exhibit weak field dependence, and scale as a function of the dot geometrical aspect ratio. The measured frequencies are well described by micromagnetic and analytical calculations that rely only on known properties of the dots (such as the dot diameter, thickness, saturation magnetization, and exchange stiffness constant) without any adjustable parameters. We find that the observed resonance originates from the translational motion of the magnetic vortex core.Comment: submitted to PRB, 17 pages, 5 Fig

WFPC2 LRF Imaging of Emission Line Nebulae in 3CR Radio Galaxies

We present HST/WFPC2 Linear Ramp Filter images of high surface brightness emission lines (either [OII], [OIII], or H-alpha+[NII]) in 80 3CR radio sources. We overlay the emission line images on high resolution VLA radio images (eight of which are new reductions of archival data) in order to examine the spatial relationship between the optical and radio emission. We confirm that the radio and optical emission line structures are consistent with weak alignment at low redshift (z < 0.6) except in the Compact Steep Spectrum (CSS) radio galaxies where both the radio source and the emission line nebulae are on galactic scales and strong alignment is seen at all redshifts. There are weak trends for the aligned emission line nebulae to be more luminous, and for the emission line nebula size to increase with redshift and/or radio power. The combination of these results suggests that there is a limited but real capacity for the radio source to influence the properties of the emission line nebulae at these low redshifts (z < 0.6). Our results are consistent with previous suggestions that both mechanical and radiant energy are responsible for generating alignment between the radio source and emission line gas.Comment: 80 pages, 54 figures. Accepted for publication in ApJ

Quantitative Dark-Field Mass Analysis of Ultrathin Cryosections in the Field-Emission Scanning Transmission Electron Microscope

The availability of a cryotransfer stage, highly efficient electron energy loss spectrometers, and ultrathin-window energy-dispersive x-ray spectrometers for the VG Microscopes HB501 field-emission scanning transmission electron microscope (STEM) provides this instrument with the potential for high resolution biological microanalysis. Recent technical advances offer cryosections that are thin enough to take advantage of the analytical capabilities of this microscope. This paper first discusses the quantitative characterization of freeze-dried, ultrathin cryosections of directly frozen liver and brain by low-dose dark-field STEM imaging. Such images reveal high-quality sections with good structural detail, mainly due to reduced preparation artifacts and electron beam damage. These sections are thin enough for dark-field mass analysis, so that the mass of individual organelles can be measured in situ, and their water content deduced. This permits the measurement of mass loss-corrected subcellular elemental concentrations. The results suggest several new applications for cryosections as illustrated by data on synaptic activity-dependent calcium regulation in Purkinje cells of mouse cerebellum. Low-dose mass analysis of cryosections in combination with x-ray and electron spectroscopy is a promising approach to quantitating physiological changes in mass distribution and elemental composition