A Delay Vector Variance based marker for an output-only assessment of structural changes in tension leg platforms

Although aspects of power generation of many offshore renewable devices are well understood, their dynamic responses under high wind and wave conditions are still to be investigated to a great detail. Output only statistical markers are important for these offshore devices, since access to the device is limited and information about the exposure conditions and the true behaviour of the devices are generally partial, limited, and vague or even absent. The markers can summarise and characterise the behaviour of these devices from their dynamic response available as time series data. The behaviour may be linear or nonlinear and consequently a marker that can track the changes in structural situations can be quite important. These markers can then be helpful in assessing the current condition of the structure and can indicate possible intervention, monitoring or assessment. This paper considers a Delay Vector Variance based marker for changes in a tension leg platform tested in an ocean wave basin for structural changes brought about by single column dampers. The approach is based on dynamic outputs of the device alone and is based on the estimation of the nonlinearity of the output signal. The advantages of the selected marker and its response with changing structural properties are discussed. The marker is observed to be important for monitoring the as- deployed structural condition and is sensitive to changes in such conditions. Influence of exposure conditions of wave loading is also discussed in this study based only on experimental data.

Predicting Forest Responses to Changing Environmental Conditions

<p>Forests change with changes in their environment based on the physiological responses of individual trees. These short-term reactions have cumulative impacts on long-term demographic performance. For a tree in a forest community, success depends on biomass growth to capture above- and belowground resources and reproductive output to establish future generations. Here we examine aspects of how forests respond to changes in moisture and light availability and how these responses are related to tree demography and physiology.</p><p>First we address the long-term pattern of tree decline before death and its connection with drought. Increasing drought stress and chronic morbidity could have pervasive impacts on forest composition in many regions. We use long-term, whole-stand inventory data from southeastern U.S. forests to show that trees exposed to drought experience multiyear declines in growth prior to mortality. Following a severe, multiyear drought, 72% of trees that did not recover their pre-drought growth rates died within 10 years. This pattern was mediated by local moisture availability. As an index of morbidity prior to death, we calculated the difference in cumulative growth after drought relative to surviving conspecifics. The strength of drought-induced morbidity varied among species and was correlated with species drought tolerance. </p><p>Next, we investigate differences among tree species in reproductive output relative to biomass growth with changes in light availability. Previous studies reach conflicting conclusions about the constraints on reproductive allocation relative to growth and how they vary through time, across species, and between environments. We test the hypothesis that canopy exposure to light, a critical resource, limits reproductive allocation by comparing long-term relationships between reproduction and growth for trees from 21 species in forests throughout the southeastern U.S. We found that species had divergent responses to light availability, with shade-intolerant species experiencing an alleviation of trade-offs between growth and reproduction at high light. Shade-tolerant species showed no changes in reproductive output across light environments. </p><p>Given that the above patterns depend on the maintenance of transpiration, we next developed an approach for predicting whole-tree water use from sap flux observations. Accurately scaling these observations to tree- or stand-levels requires accounting for variation in sap flux between wood types and with depth into the tree. We compared different models with sap flux data to test the hypotheses that radial sap flux profiles differ by wood type and tree size. We show that radial variation in sap flux is dependent on wood type but independent of tree size for a range of temperate trees. The best-fitting model predicted out-of-sample sap flux observations and independent estimates of sapwood area with small errors, suggesting robustness in new settings. We outline a method for predicting whole-tree water use with this model and include computer code for simple implementation in other studies. </p><p>Finally, we estimated tree water balances during drought with a statistical time-series analysis. Moisture limitation in forest stands comes predominantly from water use by the trees themselves, a drought-stand feedback. We show that drought impacts on tree fitness and forest composition can be predicted by tracking the moisture reservoir available to each tree in a mass balance. We apply this model to multiple seasonal droughts in a temperate forest with measurements of tree water use to demonstrate how species and size differences modulate moisture availability across landscapes. As trees deplete their soil moisture reservoir during droughts, a transpiration deficit develops, leading to reduced biomass growth and reproductive output.</p><p>This dissertation draws connections between the physiological condition of individual trees and their behavior in crowded, diverse, and continually-changing forest stands. The analyses take advantage of growing data sets on both the physiology and demography of trees as well as novel statistical techniques that allow us to link these observations to realistic quantitative models. The results can be used to scale up tree measurements to entire stands and address questions about the future composition of forests and the land���s balance of water and carbon.</p>

Non-Pharmacological Approaches for Pain Management in Sickle Cell Disease: Development of a Mindfulness-Based Intervention

<p>Background: Sickle Cell Disease (SCD) is a genetic hematological disorder that affects more than 7 million people globally (NHLBI, 2009). It is estimated that 50% of adults with SCD experience pain on most days, with 1/3 experiencing chronic pain daily (Smith et al., 2008). Persons with SCD also experience higher levels of pain catastrophizing (feelings of helplessness, pain rumination and magnification) than other chronic pain conditions, which is associated with increases in pain intensity, pain behavior, analgesic consumption, frequency and duration of hospital visits, and with reduced daily activities (Sullivan, Bishop, & Pivik, 1995; Keefe et al., 2000; Gil et al., 1992 & 1993). Therefore effective interventions are needed that can successfully be used manage pain and pain-related outcomes (e.g., pain catastrophizing) in persons with SCD. A review of the literature demonstrated limited information regarding the feasibility and efficacy of non-pharmacological approaches for pain in persons with SCD, finding an average effect size of .33 on pain reduction across measurable non-pharmacological studies. Second, a prospective study on persons with SCD that received care for a vaso-occlusive crisis (VOC; N = 95) found: (1) high levels of patient reported depression (29%) and anxiety (34%), and (2) that unemployment was significantly associated with increased frequency of acute care encounters and hospital admissions per person. Research suggests that one promising category of non-pharmacological interventions for managing both physical and affective components of pain are Mindfulness-based Interventions (MBIs; Thompson et al., 2010; Cox et al., 2013). The primary goal of this dissertation was thus to develop and test the feasibility, acceptability, and efficacy of a telephonic MBI for pain catastrophizing in persons with SCD and chronic pain. </p><p>Methods: First, a telephonic MBI was developed through an informal process that involved iterative feedback from patients, clinical experts in SCD and pain management, social workers, psychologists, and mindfulness clinicians. Through this process, relevant topics and skills were selected to adapt in each MBI session. Second, a pilot randomized controlled trial was conducted to test the feasibility, acceptability, and efficacy of the telephonic MBI for pain catastrophizing in persons with SCD and chronic pain. Acceptability and feasibility were determined by assessment of recruitment, attrition, dropout, and refusal rates (including refusal reasons), along with semi-structured interviews with nine randomly selected patients at the end of study. Participants completed assessments at baseline, Week 1, 3, and 6 to assess efficacy of the intervention on decreasing pain catastrophizing and other pain-related outcomes. </p><p>Results: A telephonic MBI is feasible and acceptable for persons with SCD and chronic pain. Seventy-eight patients with SCD and chronic pain were approached, and 76% (N = 60) were enrolled and randomized. The MBI attendance rate, approximately 57% of participants completing at least four mindfulness sessions, was deemed acceptable, and participants that received the telephonic MBI described it as acceptable, easy to access, and consume in post-intervention interviews. The amount of missing data was undesirable (MBI condition, 40%; control condition, 25%), but fell within the range of expected missing outcome data for a RCT with multiple follow-up assessments. Efficacy of the MBI on pain catastrophizing could not be determined due to small sample size and degree of missing data, but trajectory analyses conducted for the MBI condition only trended in the right direction and pain catastrophizing approached statistically significance. </p><p>Conclusion: Overall results showed that at telephonic group-based MBI is acceptable and feasible for persons with SCD and chronic pain. Though the study was not able to determine treatment efficacy nor powered to detect a statistically significant difference between conditions, participants (1) described the intervention as acceptable, and (2) the observed effect sizes for the MBI condition demonstrated large effects of the MBI on pain catastrophizing, mental health, and physical health. Replication of this MBI study with a larger sample size, active control group, and additional assessments at the end of each week (e.g., Week 1 through Week 6) is needed to determine treatment efficacy. Many lessons were learned that will guide the development of future studies including which MBI strategies were most helpful, methods to encourage continued participation, and how to improve data capture.</p>

Rightful Resistance in the Colombian conflict. A theoretical reflection based on a Peace Community

This article considers the opportunities of civilians to peacefully resist violent conflicts or civil wars. The argument developed here is based on a field-based research on the peace community San Jos�� de Apartad�� in Colombia. The analytical and theoretical framework, which delimits the use of the term ���resistance��� in this article, builds on the conceptual considerations of Hollander and Einwohner (2004) and on the theoretical concept of ���rightful resistance��� developed by O���Brien (1996). Beginning with a conflict-analytical classification of the case study, we will describe the long-term socio-historical processes and the organizational experiences of the civilian population, which favoured the emergence of this resistance initiative. The analytical approach to the dimensions and aims of the resistance of this peace community leads to the differentiation of O`Brian���s concept of ���rightful resistance���.

Natriuretic peptide-based screening and collaborative care for heart failure:the STOP-HF randomized trial

<p>IMPORTANCE: Prevention strategies for heart failure are needed.</p><p>OBJECTIVE: To determine the efficacy of a screening program using brain-type natriuretic peptide (BNP) and collaborative care in an at-risk population in reducing newly diagnosed heart failure and prevalence of significant left ventricular (LV) systolic and/or diastolic dysfunction.</p><p>DESIGN, SETTING, AND PARTICIPANTS: The St Vincent's Screening to Prevent Heart Failure Study, a parallel-group randomized trial involving 1374 participants with cardiovascular risk factors (mean age, 64.8 [SD, 10.2] years) recruited from 39 primary care practices in Ireland between January 2005 and December 2009 and followed up until December 2011 (mean follow-up, 4.2 [SD, 1.2] years).</p><p>INTERVENTION: Patients were randomly assigned to receive usual primary care (control condition; n=677) or screening with BNP testing (n=697). Intervention-group participants with BNP levels of 50 pg/mL or higher underwent echocardiography and collaborative care between their primary care physician and specialist cardiovascular service.</p><p>MAIN OUTCOMES AND MEASURES: The primary end point was prevalence of asymptomatic LV dysfunction with or without newly diagnosed heart failure. Secondary end points included emergency hospitalization for arrhythmia, transient ischemic attack, stroke, myocardial infarction, peripheral or pulmonary thrombosis/embolus, or heart failure.</p><p>RESULTS: A total of 263 patients (41.6%) in the intervention group had at least 1 BNP reading of 50 pg/mL or higher. The intervention group underwent more cardiovascular investigations (control, 496 per 1000 patient-years vs intervention, 850 per 1000 patient-years; incidence rate ratio, 1.71; 95% CI, 1.61-1.83; P&lt;.001) and received more renin-angiotensin-aldosterone system-based therapy at follow-up (control, 49.6%; intervention, 56.5%; P=.01). The primary end point of LV dysfunction with or without heart failure was met in 59 (8.7%) of 677 in the control group and 37 (5.3%) of 697 in the intervention group (odds ratio [OR], 0.55; 95% CI, 0.37-0.82; P���=���.003). Asymptomatic LV dysfunction was found in 45 (6.6%) of 677 control-group patients and 30 (4.3%) of 697 intervention-group patients (OR, 0.57; 95% CI, 0.37-0.88; P���=���.01). Heart failure occurred in 14 (2.1%) of 677 control-group patients and 7 (1.0%) of 697 intervention-group patients (OR, 0.48; 95% CI, 0.20-1.20; P���=���.12). The incidence rates of emergency hospitalization for major cardiovascular events were 40.4 per 1000 patient-years in the control group vs 22.3 per 1000 patient-years in the intervention group (incidence rate ratio, 0.60; 95% CI, 0.45-0.81; P���=���.002).</p><p>CONCLUSION AND RELEVANCE: Among patients at risk of heart failure, BNP-based screening and collaborative care reduced the combined rates of LV systolic dysfunction, diastolic dysfunction, and heart failure.</p><p>TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00921960.</p>

Chloride ingress into marine exposed concrete: A comparison of empirical- and physically- based models

In establishing the reliability of performance-related design methods for concrete ��� which are relevant for resistance against chloride-induced corrosion - long-term experience of local materials and practices and detailed knowledge of the ambient and local micro-climate are critical. Furthermore, in the development of analytical models for performance-based design, calibration against test data representative of actual conditions in practice is required. To this end, the current study presents results from full-scale, concrete pier-stems under long-term exposure to a marine environment with work focussing on XS2 (below mid-tide level) in which the concrete is regarded as fully saturated and XS3 (tidal, splash and spray) in which the concrete is in an unsaturated condition. These exposures represent zones where concrete structures are most susceptible to ionic ingress and deterioration. Chloride profiles and chloride transport behaviour are studied using both an empirical model (erfc function) and a physical model (ClinConc). The time dependency of surface chloride concentration (Cs) and apparent diffusivity (Da) were established for the empirical model whereas, in the ClinConc model (originally based on saturated concrete), two new environmental factors were introduced for the XS3 environmental exposure zone. Although the XS3 is considered as one environmental exposure zone according to BS EN 206-1:2013, the work has highlighted that even within this zone, significant changes in chloride ingress are evident. This study aims to update the parameters of both models for predicting the long term transport behaviour of concrete subjected to environmental exposure classes XS2 and XS3.

A comparison of individual cow versus group concentrate allocation strategies on dry matter intake, milk production, tissue changes, and fertility of Holstein-Friesian cows offered a grass silage diet

A diverse range of concentrate allocation strategies are adopted on dairy farms. The objectives of this study were to examine the effects on cow performance [dry matter (DM) intake (DMI), milk yield and composition, body tissue changes, and fertility] of adopting 2 contrasting concentrate allocation strategies over the first 140 d of lactation. Seventy-seven Holstein-Friesian dairy cows were allocated to 1 of 2 concentrate allocation strategies at calving, namely group or individual cow. Cows on the group strategy were offered a mixed ration comprising grass silage and concentrates in a 50:50 ratio on a DM basis. Cows on the individual cow strategy were offered a basal mixed ration comprising grass silage and concentrates (the latter included in the mix to achieve a mean intake of 6���kg/cow per day), which was formulated to meet the cow���s energy requirements for maintenance plus 24���kg of milk/cow per day. Additional concentrates were offered via an out-of-parlor feeding system, with the amount offered adjusted weekly based on each individual cow���s milk yield during the previous week. In addition, all cows received a small quantity of straw in the mixed ration part of the diet (approximately 0.3���kg/cow per day), plus 0.5���kg of concentrate twice daily in the milking parlor. Mean concentrate intakes over the study period were similar with each of the 2 allocation strategies (11.5 and 11.7���kg of DM/cow per day for group and individual cow, respectively), although the pattern of intake with each treatment differed over time. Concentrate allocation strategy had no effect on either milk yield (39.3 and 38.0���kg/d for group and individual cow, respectively), milk composition, or milk constituent yield. The milk yield response curves with each treatment were largely aligned with the concentrate DMI curves. Cows on the individual cow treatment had a greater range of concentrate DMI and milk yields than those on the group treatment. With the exception of a tendency for cows on the individual cow treatment to lose more body weight to nadir than cows on the group treatment, concentrate allocation strategy had little effect on either body weight or body condition score over the experimental period. Cows on the individual cow treatment had a higher pregnancy rate to first and second service and tended to have a higher 100-d in calf rate than cows on the group treatment. This study demonstrates that concentrate allocation strategy had little effect on overall production performance.

Effectiveness and cost-effectiveness of a physical activity loyalty scheme for behaviour change maintenance: a cluster randomised controlled trial

Background<br/>Increasing physical activity in the workplace can provide employee physical and mental health benefits, and employer economic benefits through reduced absenteeism and increased productivity. The workplace is an opportune setting to encourage habitual activity. However, there is limited evidence on effective behaviour change interventions that lead to maintained physical activity. This study aims to address this gap and help build the necessary evidence base for effective, and cost-effective, workplace interventions<br/><br/>Methods/design<br/>This cluster randomised control trial will recruit 776 office-based employees from public sector organisations in Belfast and Lisburn city centres, Northern Ireland. Participants will be randomly allocated by cluster to either the Intervention Group or Control Group (waiting list control). The 6-month intervention consists of rewards (retail vouchers, based on similar principles to high street loyalty cards), feedback and other evidence-based behaviour change techniques. Sensors situated in the vicinity of participating workplaces will promote and monitor minutes of physical activity undertaken by participants. Both groups will complete all outcome measures. The primary outcome is steps per day recorded using a pedometer (Yamax Digiwalker CW-701) for 7 consecutive days at baseline, 6, 12 and 18 months. Secondary outcomes include health, mental wellbeing, quality of life, work absenteeism and presenteeism, and use of healthcare resources. Process measures will assess intervention ���dose���, website usage, and intervention fidelity. An economic evaluation will be conducted from the National Health Service, employer and retailer perspective using both a cost-utility and cost-effectiveness framework. The inclusion of a discrete choice experiment will further generate values for a cost-benefit analysis. Participant focus groups will explore who the intervention worked for and why, and interviews with retailers will elucidate their views on the sustainability of a public health focused loyalty card scheme.<br/><br/>Discussion<br/>The study is designed to maximise the potential for roll-out in similar settings, by engaging the public sector and business community in designing and delivering the intervention. We have developed a sustainable business model using a ���points��� based loyalty platform, whereby local businesses ���sponsor��� the incentive (retail vouchers) in return for increased footfall to their business.<br/><br/>

The Clinical Impact and Molecular Biology of del(17p) in Multiple Myeloma Treated with Conventional or Thalidomide-Based Therapy

Hemizygous deletion of 17p (del(17p)) has been identified as a variable associated with poor prognosis in myeloma, although its impact in the context of thalidomide therapy is not well described. The clinical outcome of 85 myeloma patients with del(17p) treated in a clinical trial incorporating both conventional and thalidomide-based induction therapies was examined. The clinical impact of deletion, low expression, and mutation of TP53 was also determined. Patients with del(17p) did not have inferior response rates compared to patients without del(17p), but, despite this, del(17p) was associated with impaired overall survival (OS) (median OS 26.6 vs. 48.5 months, P &lt;0.001). Within the del(17p) group, thalidomide induction therapy was associated with improved response rates compared to conventional therapy, but there was no impact on OS. Thalidomide maintenance was associated with impaired OS, although our analysis suggests that this effect may have been due to confounding variables. A minimally deleted region on 17p13.1 involving 17 genes was identified, of which only TP53 and SAT2 were underexpressed. TP53 was mutated in &lt;1% in patients without del(17p) and in 27% of patients with del(17p). The higher TP53 mutation rate in samples with del(17p) suggests a role for TP53 in these clinical outcomes. In conclusion, del(17p) defined a patient group associated with short survival in myeloma, and although thalidomide induction therapy was associated with improved response rates, it did not impact OS, suggesting that alternative therapeutic strategies are required for this group. (C) 2011 Wiley-Liss, Inc.

Tribologische Echtzeit��berwachung in F��rdersystemen

Echtzeitbasierte Anlagen��berwachung gewinnt in industrieller Umgebung zunehmend an Bedeutung. Die fr��hzeitige Erfassung von St��rungen erm��glicht es Unternehmen Anlagen punktgenau zu warten und somit deren Stillstandszeiten zu reduzieren. Auch im Bereich der F��rdertechnik sind diese Systeme er-w��nscht, aber aufgrund des beengten Bauraums ge-staltet sich ihre Integration oftmals schwierig. Im Fol-genden wird eine Baugruppe vorgestellt, welche das Reibwert- und Schmierstoffverhalten f��rdertechni-scher Anlagen in Echtzeit erfassen kann.

Wavelength converters based on four-wave mixing in semiconductor optical amplifiers for advanced modulation formats

Les convertisseurs de longueur d���onde sont essentiels pour la r��alisation de r��seaux de communications optiques �� routage en longueur d���onde. Dans la litt��rature, les convertisseurs de longueur d���onde bas��s sur le m��lange �� quatre ondes dans les amplificateurs optiques �� semi-conducteur constituent une solution extr��mement int��ressante, et ce, en raison de leurs nombreuses caract��ristiques n��cessaires �� l���impl��mentation de tels r��seaux de communications. Avec l�����mergence des syst��mes commerciaux de d��tection coh��rente, ainsi qu���avec les r��centes avanc��es dans le domaine du traitement de signal num��rique, il est imp��ratif d�����valuer la performance des convertisseurs de longueur d���onde, et ce, dans le contexte des formats de modulation avanc��s. Les objectifs de cette th��se sont : 1) d�����tudier la faisabilit�� des convertisseurs de longueur d���onde bas��s sur le m��lange �� quatre ondes dans les amplificateurs optiques �� semi-conducteur pour les formats de modulation avanc��s et 2) de proposer une technique bas��e sur le traitement de signal num��rique afin d���am��liorer leur performance. En premier lieu, une ��tude exp��rimentale de la conversion de longueur d���onde de formats de modulation d���amplitude en quadrature (quadrature amplitude modulation - QAM) est r��alis��e. En particulier, la conversion de longueur d���onde de signaux 16-QAM �� 16 Gbaud et 64-QAM �� 5 Gbaud dans un amplificateur optique �� semi-conducteur commercial est r��alis��e sur toute la bande C. Les r��sultats d��montrent qu���en raison des distorsions non-lin��aires induites sur le signal converti, le point d���op��ration optimal du convertisseur de longueur d���onde est diff��rent de celui obtenu lors de la conversion de longueur d���onde de formats de modulation en intensit��. En effet, dans le contexte des formats de modulation avanc��s, c���est le compromis entre la puissance du signal converti et les non-lin��arit��s induites qui d��termine le point d���op��ration optimal du convertisseur de longueur d���onde. Les r��cepteurs coh��rents permettent l���utilisation de techniques de traitement de signal num��rique afin de compenser la d��t��rioration du signal transmis suite �� sa d��tection. Afin de mettre �� profit les nouvelles possibilit��s offertes par le traitement de signal num��rique, une technique num��rique de post-compensation des distorsions induites sur le signal converti, bas��e sur une analyse petit-signal des ��quations gouvernant la dynamique du gain �� l���int��rieur des amplificateurs optiques �� semi-conducteur, est d��velopp��e. L���efficacit�� de cette technique est d��montr��e �� l���aide de simulations num��riques et de mesures exp��rimentales de conversion de longueur d���onde de signaux 16-QAM �� 10 Gbaud et 64-QAM �� 5 Gbaud. Cette m��thode permet d���am��liorer de fa��on significative les performances du convertisseur de longueur d���onde, et ce, principalement pour les formats de modulation avanc��s d���ordre sup��rieur tel que 64-QAM. Finalement, une ��tude exp��rimentale exhaustive de la technique de post-compensation des distorsions induites sur le signal converti est effectu��e pour des signaux 64-QAM. Les r��sultats d��montrent que, m��me en pr��sence d���un signal �� bruit�� �� l���entr��e du convertisseur de longueur d���onde, la technique propos��e am��liore toujours la qualit�� du signal re��u. De plus, une ��tude du point d���op��ration optimal du convertisseur de longueur d���onde est effectu��e et d��montre que celui-ci varie en fonction des pertes optiques suivant la conversion de longueur d���onde. Dans un r��seau de communication optique �� routage en longueur d���onde, le signal est susceptible de passer par plusieurs ��tages de conversion de longueur d���onde. Pour cette raison, l���efficacit�� de la technique de post-compensation est d��montr��e, et ce pour la premi��re fois dans la litt��rature, pour deux ��tages successifs de conversion de longueur d���onde de signaux 64-QAM �� 5 Gbaud. Les r��sultats de cette th��se montrent que les convertisseurs de longueur d���ondes bas��s sur le m��lange �� quatre ondes dans les amplificateurs optiques �� semi-conducteur, utilis��s en conjonction avec des techniques de traitement de signal num��rique, constituent une technologie extr��mement prometteuse pour les r��seaux de communications optiques modernes �� routage en longueur d���onde.

Finite Element Modeling of Spiral Frequency Steerable Acoustic Transducers (FSATs) for guided waves based Structural Health Monitoring of plate-like structures

Structural Health Monitoring (SHM) is an emerging area of research associated to improvement of maintainability and the safety of aerospace, civil and mechanical infrastructures by means of monitoring and damage detection. Guided wave structural testing method is an approach for health monitoring of plate-like structures using smart material piezoelectric transducers. Among many kinds of transducers, the ones that have beam steering feature can perform more accurate surface interrogation. A frequency steerable acoustic transducer (FSATs) is capable of beam steering by varying the input frequency and consequently can detect and localize damage in structures. Guided wave inspection is typically performed through phased arrays which feature a large number of piezoelectric transducers, complexity and limitations. To overcome the weight penalty, the complex circuity and maintenance concern associated with wiring a large number of transducers, new FSATs are proposed that present inherent directional capabilities when generating and sensing elastic waves. The first generation of Spiral FSAT has two main limitations. First, waves are excited or sensed in one direction and in the opposite one (180 �� ambiguity) and second, just a relatively rude approximation of the desired directivity has been attained. Second generation of Spiral FSAT is proposed to overcome the first generation limitations. The importance of simulation tools becomes higher when a new idea is proposed and starts to be developed. The shaped transducer concept, especially the second generation of spiral FSAT is a novel idea in guided waves based of Structural Health Monitoring systems, hence finding a simulation tool is a necessity to develop various design aspects of this innovative transducer. In this work, the numerical simulation of the 1st and 2nd generations of Spiral FSAT has been conducted to prove the directional capability of excited guided waves through a plate-like structure.

The disappearing of palheiros in Aveiro lagoon

Palheiros are traditional timber constructions existing in the littoral centre region of Portugal. This is particularly the case of the Aveiro lagoon region where for many years many such constructions have existed. They were originally built to store working tools related with lagoon activity (fishing and sea salt extraction) and to give shelter for the fishermen during the fishing season. These constructions were built with superimposed veneers in vertical or horizontal directions. Since they are mostly located near the sea, they have started to be used as holiday houses and are often painted in vivid colours. Most of these buildings are being replaced by concrete constructions, since their preservation state is rather unsatisfactory or simply because there is a need to increase their size. Additionally, little knowledge about the possibilities of maintenance and building in timber structures exists. In some cases, although the structures were changed from timber to concrete, the exterior appearance of the palheiros remains the same, which might be interesting from the pictorial point of view but it isn���t certainly from a heritage preservation perspective. However in many other situations, they are being substituted by ���modern��� constructions that were not valuable in any of the previous viewpoints. Fortunately, there are also cases where palheiros have been preserved and remain in good condition. For how long these examples will remain is certainly the major question that must be answered since these are only on the dependence of owner���s will and not based on local authorities concern. A consciousness of local authorities and citizens is mandatory in order to preserve this heritage because it is perfectly possible to preserve the traditional constructions offering all the comfort of modern houses. Keywords: timber construction, vernacular construction, preservation.

PORBS: A parallel observation-based slicer

Abstract���This paper presents PORBS, a parallelised observation-based slicing tool. The tool itself is written in Java making it platform independent and leverages the build chain of the system being sliced to avoid the need to replicate complex compiler analysis. The target audience of PORBS is software engineers and researchers working with and on tools and techniques for software comprehension, debugging, re-engineering, and maintenance.

Towards a performance based design of shear walls based on damage criteria = Vers un dimensionnement performanciel des murs de refend bas�� sur des crit��res d'endommagement

Le dimensionnement bas�� sur la performance (DBP), dans une approche d��terministe, caract��rise les objectifs de performance par rapport aux niveaux de performance souhait��s. Les objectifs de performance sont alors associ��s �� l'��tat d'endommagement et au niveau de risque sismique ��tablis. Malgr�� cette approche rationnelle, son application est encore difficile. De ce fait, des outils fiables pour la capture de l'��volution, de la distribution et de la quantification de l'endommagement sont n��cessaires. De plus, tous les ph��nom��nes li��s �� la non-lin��arit�� (mat��riaux et d��formations) doivent ��galement ��tre pris en consid��ration. Ainsi, cette recherche montre comment la m��canique de l'endommagement pourrait contribuer �� r��soudre cette probl��matique avec une adaptation de la th��orie du champ de compression modifi��e et d'autres th��ories compl��mentaires. La formulation propos��e adapt��e pour des charges monotones, cycliques et de type pushover permet de consid��rer les effets non lin��aires li��s au cisaillement coupl�� avec les m��canismes de flexion et de charge axiale. Cette formulation est sp��cialement appliqu��e �� l'analyse non lin��aire des ��l��ments structuraux en b��ton soumis aux effets de cisaillement non ��gligeables. Cette nouvelle approche mise en ��uvre dans EfiCoS (programme d'��l��ments finis bas�� sur la m��canique de l'endommagement), y compris les crit��res de mod��lisation, sont ��galement pr��sent��s ici. Des calibrations de cette nouvelle approche en comparant les pr��dictions avec des donn��es exp��rimentales ont ��t�� r��alis��es pour les murs de refend en b��ton arm�� ainsi que pour des poutres et des piliers de pont o�� les effets de cisaillement doivent ��tre pris en consid��ration. Cette nouvelle version am��lior��e du logiciel EFiCoS a d��montr��e ��tre capable d'��valuer avec pr��cision les param��tres associ��s �� la performance globale tels que les d��placements, la r��sistance du syst��me, les effets li��s �� la r��ponse cyclique et la quantification, l'��volution et la distribution de l'endommagement. Des r��sultats remarquables ont ��galement ��t�� obtenus en r��f��rence �� la d��tection appropri��e des ��tats limites d'ing��nierie tels que la fissuration, les d��formations unitaires, l'��clatement de l'enrobage, l'��crasement du noyau, la plastification locale des barres d'armature et la d��gradation du syst��me, entre autres. Comme un outil pratique d'application du DBP, des relations entre les indices d'endommagement pr��dits et les niveaux de performance ont ��t�� obtenus et exprim��s sous forme de graphiques et de tableaux. Ces graphiques ont ��t�� d��velopp��s en fonction du d��placement relatif et de la ductilit�� de d��placement. Un tableau particulier a ��t�� d��velopp�� pour relier les ��tats limites d'ing��nierie, l'endommagement, le d��placement relatif et les niveaux de performance traditionnels. Les r��sultats ont d��montr�� une excellente correspondance avec les donn��es exp��rimentales, faisant de la formulation propos��e et de la nouvelle version d'EfiCoS des outils puissants pour l'application de la m��thodologie du DBP, dans une approche d��terministe.